Effects of Differential
Status of Group Members
on Process and Outcome
of Deliberation

Martin F. Kaplan

Northern Illinois University

Ana M. Martin

Universidad de La Laguna

Decision making groups, including European juries, often contain factions differing in status.
Mock juries composed of trained and layperson status factions decided guilt and punishment
for realistic cases of university code violations. Cases presented predominantly intellective or
judgmental issues, and juries had to justify verdicts according to facts alone, or facts and values.
Compared to laypersons, trained factions influenced group decisions more, but only in
judgmental cases, or when having to include values in justification. They more actively
discussed the judgmental cases, and engaged more than laypersons in normative influence.
Trained jurors appear to wield social/normative power, impacting judgmental issues more.
Consistent with their minority status, laypersons engage in more informational than normative
influence. The fact that laypersons are as active in discussing intellective cases as are trained
members, and are equally informational in their style of influence, enhances their impact when
deciding issues that revolve around gathering facts to reach a correct decision.

keywords

factions, groups, influence, processes, status

Group Processes &

Intergroup Relations

1999 Vol 2(4) 347–364

Decision making groups are often composed
of members who differ in status characteristics
that are relevant to the decision task. One
notable example is the jury in many European
countries, which consists of a mixture of lay and
professional jurors. In France, Germany, Italy,
Hungary, Poland, and Switzerland, juries are
composed by statute of laypersons and trained
judges (the escabinado model) so that faction
differences in power and status are potentially
created. Preference for mixed or ‘pure’ lay
juries is based on social, political, and jurispru-

dence reasons, and not on empirical conse-
quences (Munday, 1993). In fact, few empirical
studies of the dynamics and outcomes of mixed

G

P

I

R

Copyright © 1999 SAGE Publications

(London, Thousand Oaks, CA and New Delhi)

[1368-4302(199910)2:4; 347–364; 009681]

Author’s note
Address correspondence to Martin F. Kaplan,
Department of Psychology, Northern Illinois
University, DeKalb, IL 60115, USA. [email
[e-mail].]

juries have been reported despite the intuitively
obvious effects of differential status.

The pure lay jury that has been traditional in

the Anglo-American tradition is under severe
attack, with calls regularly heard for either the
substitution of juries wholly or partly consisting
of experts, or for elimination of juries in gen-
eral (see Munday, 1993; Nemeth, 1985). A good
illustration of the debate can be seen in the
recent adoption by Spain of a pure jury, but
with very limited powers and jurisdiction (see
Kaplan & Martin, 1999, for an account of the
protracted debate on a pure vs. escabinado jury
in Spain). The challenge to pure juries having
broad powers remains unabated, while recourse
to mixed juries with professional judges who
rein in the power of lay persons continues to be
a strong alternative. Thus, in empirically com-
paring the two forms of juries, the question of
whether trained jurors produce an imbalance
in influence is important.

The present research asks whether the pres-

ence of lay and trained factions results in an
imbalance of power in determining a consensus
decision, and whether lay and trained jurors use
different means of influencing the decision.
This study focuses on the psychological conse-
quences of such jury factions for influence style
and effectiveness, and is not intended to
address the broader comparisons of the pure
Anglo-American model to the continental
European escabinado model. That is, empirical
study of the social psychology of mixed juries,
and the sociopolitical considerations that may
or may not recommend them, are distinct mat-
ters.

Empirical studies of mixed juries tell us little

about the differential role of lay and trained fac-
tions in such juries. It has been shown, for
example, that lay persons attribute greater
expertise to judges in mixed juries in Germany
(Brandstatter, Bleckwenn, & Kette, 1984) but
that does not insure that judges will be more
influential, or that their means of influencing
will be qualitatively different than those of
laypersons. Though there is statistical evidence
that judges are more influential in deciding ver-
dicts than lay jury members in German courts
(Casper & Zeisel, 1972), we do not know the

means by which judges were more influential,
whether it depended on the sort of case being
considered, and whether the greater power of
professional judges can be curtailed. Nor do the
few experimental studies of mixed juries yield a
clear or consistent picture of the relative influ-
ence and different influence tactics of expert
and lay factions. Palmer (1988) compared pure
and mixed mock juries for the extent of change
in their verdicts in criminal cases after delibera-
tion. Mixed juries changed more than did pure
juries, and in opposite directions; the former
became more stringent, and the latter became
more lenient following deliberation. But this
outcome may be unique to the particular case
that was employed, and tells nothing about the
dynamics of deliberation, and the sorts and
extents of influence practiced by factions in the
mixed juries. The outcome is further weakened
by contrary findings (Cajal-Blanco, 1994) of
greater leniency shift by mixed juries, but only
in an armed robbery case, with no differences
between juries in a rape or a manslaughter case.
It is clear that research is needed to examine
the relative influence of the trained and lay fac-
tions within mixed juries, potential differences
in the dynamics of the deliberation process, and
whether such differences in influence and
process can vary with the sorts of issues and
cases being decided. No research exists which
directly addresses these questions in mixed
juries. However, studies of influence processes
in general are relevant to the dynamics of such
juries, particularly with reference to the sorts of
influence tactics that emerge during discussion
(e.g. Kaplan, 1989), and the exercise of power
within groups (e.g. French & Raven, 1959).

Influence within decision making groups can

take a social or cognitive form. That is, group
members may try to influence one another
based on relations among members, or on facts
regarding the issue. In group dynamics, norma-
tive influence is a social-relational form of influ-
ence in which pressure is applied to conform to
the positive expectations of others (Deutsch &
Gerard, 1955). The group, by its expressed pref-
erences for an outcome, conveys a norm, and
deviant members are influenced to accept that
decision because it is a group norm (for present

Group Processes & Intergroup Relations 2(4)

348

purposes, the motives for normative conformity
are not relevant). Informational influence
refers to influence to accept information
obtained from others as evidence about reality
(Deutsch & Gerard, 1955). In other words,
influence and change are due to cognitive
changes that result from incorporation of
facts/information about the issue. It would
seem likely that trained or professional jurors
would differ from lay jurors in the manner in
which they try to influence, and in the relative
effectiveness of the two forms of influence. But
the direction of these differences is not clear.
On the one hand, the trained jurors have more
social power, and whether in a numerical
majority or not, they may be considered to have
legitimate power (French & Raven, 1959). The
strength of a majority lies in its prescriptive or
normative power, whereas the strength of a
minority resides in its ability to focus the group
on facts that support its position (Moscovici,
1985). Given this consideration, trained jurors
would capitalize on their prestige, tending
more toward normative influence, whereas lay
jurors, who do not possess normative strength
within the group, would rely more on informa-
tional influence. On the other hand, lay jurors
possess normative strength by virtue of their
selection as representatives of the greater com-
munity, that is, they can view themselves as
reflecting norms outside the group. Moreover,
trained jurors should be more conversant with
the law and its application. Therefore, if lay and
trained jurors interpret their roles in different
ways, such roles can lead to a tendency toward
normative influence in the former faction, and
informational influence in the latter faction.
Opposite predictions regarding the preferred
mode of influence can be made depending on
whether we consider the natural power of
trained vs. lay jurors or the roles they are likely
to adopt in the judicial setting.

General tendencies of the two factions aside,

it is important to take account of the issues pre-
sented by the case being decided. Task and situ-
ational factors, such as the issue being decided
and the interactive goal of the group (task vs.
group oriented) can focus members either on
the task of reaching a correct decision, or on

the group’s relations (Kaplan, 1989). The
former will enhance the use of informational
influence, the latter will evoke more normative
influence (Kaplan, 1989). The case being
decided, for example, can present issues rang-
ing from intellective to judgmental (Laughlin &
Ellis, 1986). Intellective issues are those for
which there is a demonstrably correct solution
within a consensual conceptual system.
Definition of terms is not in question, and the
solution depends on acquiring facts. For
example, if the case involves destruction of
property, jurors can agree on what constitutes
destruction of property, and factual evidence
must be gathered on the ability, opportunity,
and motivation of the defendant to commit the
act. Judgmental issues call for evaluative prefer-
ences such as ethical, behavioral, and aesthetic
judgments. Unlike intellective issues, there are
differences in definition of terms. For example,
in a sexual harassment case, there may be dif-
ferences over whether a particular act consti-
tutes harassment, or is legally and ethically
wrong, and less so over whether it occurred or
whether the defendant engaged in the act. The
distinction is that the former focuses the group
on finding the correct decision that is sup-
ported by the facts, whereas the latter invokes
concern with the preferred solution. Of course,
many scenarios present a mixed appearance of
intellective and judgmental, but it is possible to
have instances that are predominantly one or
the other, as was assured in this study via exten-
sive pretesting. Intellective issues, therefore,
require marshaling facts via informational influ-
ence, and judgmental issues require consensus
or appeal to norms since there is no factually
demonstrable solution (Kaplan & Miller, 1987;
Kaplan, Schaefer, & Zinkiewicz, 1994). In turn,
informational influence is more effective in
producing vote changes when members are
concerned with correctness (e.g. when the issue
is intellective), and normative influence is more
effective in changing votes when the concern is
with reaching consensus in preferences
(Kaplan et al., 1994; Rugs & Kaplan, 1993). The
powerful lesson is that the effectiveness of argu-
ments by trained vs. lay jurors may depend on
the sorts of arguments they use – informational

Kaplan & Martin

mixed groups

349

or normative – and which type of case they are
deciding – intellective or judgmental.

Additional direction can be gained by con-

sidering the status and power differences
between trained and lay jurors. Note first that
higher social status confers impressions of
greater self-confidence (Nemeth & Wachtler,
1974; Sev’er, 1989), expertise (Nemeth, 1985),
and competence (Kirchler & Davis, 1986;
Sampson, 1969). In the same vein, high status is
a positive attribute, and is expected to be corre-
lated with the positive attribute of nonconfor-
mity, thus leading group members to expect
high status factions to be less pliant (Wilke,
1996). Finally, high status people participate
more in discussion (Skvoretz, 1988). These
qualities, whether real or expected, lead to
greater influence by high status members of
groups (Back & Davis, 1965; Gerbasi,
Zuckerman, & Reis, 1977; Hastie, Penrod, &
Pennington, 1983; Ridgeway, Berger, & Smith,
1985; Strodtbeck, James, & Hawkins, 1957).
Because people of similar status tend to coa-
lesce around their shared social identity, there
is a strong likelihood that high and low status
members will form distinctive factions in juries
where the status differences are related to the
task, thereby accentuating the status differences
and the influence disparity they promote
(Sachdev & Bourhis, 1991). But should the
influence advantage of high status trained
jurors be constant? Not necessarily. Kirchler
and Davis (1986) report that in an intellective
or ‘truth-wins’ task, status is irrelevant to influ-
ence, whereas in a judgmental task, high status
members are more influential. They reason that
status is more important in the latter sort of task
because the perceived competence of high
status members imparts more normative weight
to their preferences, and as we have seen, judg-
mental tasks are more susceptible to normative
influence. Thus, the Kirchler and Davis findings
suggest that when status imparts social cachet, it
will promote more influence in those tasks and
issues which are resolved by appeal to norms.

Trained or professional jurors may differ

from lay jurors in not only social status, but in
the basis of power as well. French and Raven’s
(1959) taxonomy of interpersonal power

includes two bases which are relevant to trained
jurors. Expert power refers to special knowl-
edge or expertise about the issue, and may be
related to influence via ability to provide infor-
mation about the issues and the law. This sort of
power may be assigned to trained jurors; lay
persons attribute more expertise to their judge
colleagues in German courts (Brandstatter et
al., 1984). If this is so, trained jurors should be
especially influential in cases which predomi-
nantly present intellective issues. Legitimate
power consists of the right to prescribe and
influence behavior by virtue of the person’s role
vis-a-vis the topic. Thus, if trained jurors are
ascribed legitimate power, they would have
greater power to influence votes in judgmental
issues via more normative power. Thus, depend-
ing on whether trained jurors possess expert or
legitimate power, they will be more influential
in intellective or judgmental types of cases,
respectively. The type and extent of power
wielded by each faction in a particular task is, in
the last analysis, an empirical question that can
be determined in the present study.

Another avenue to power is minority vs.

majority status of the faction. Because of their
natural advantage in power, we are considering
the trained juror faction to be analogous to
majorities in groups, whatever their numerical
strength. This presumption is not essential to
the logic of this study; whether the trained fac-
tion ‘behaves’ like a majority in terms of relative
influence and activity can be empirically
observed, and is in fact the subject of this study.
It has been shown that minorities produce
more divergent thinking (Nemeth, 1986) and
cognitive activity (Maass & Clark, 1983), and
consequently get their persuasive power from
providing information (Moscovici, 1985; Wood,
Lundgren, Ouelette, Busceme, & Blackstone,
1994). Majorities, on the other hand, having
their strength in normative power, use both
normative and informational influence (Insko,
Smith, Alicke, Wade, & Taylor, 1985). Trained
jurors, who are the status and power majority,
would be more likely to use normative influ-
ence than lay (minority) jurors, who, lacking
normative power, would rely on informational
influence. Since normative influence is more

Group Processes & Intergroup Relations 2(4)

350

effective in judgmental issues, and informa-
tional influence is more effective in intellective
issues (Rugs & Kaplan, 1993), trained jurors
should be most influential in judgmental cases,
though influential in intellective cases to a
lesser degree.

The foregoing discussion of types of influ-

ence (normative vs. informational), status, and
power argues for a study which crosses expertise
of factions (trained vs. lay jurors) with type of
issues in the case ( judgmental vs. intellective)
to observe effects on modes of influence as well
as relative extent of influence in mixed juries.
Moreover, because the focus of the groups’ task
also determines the type of influence used
(Kaplan et al., 1994) and its effectiveness on
change (Rugs & Kaplan, 1993), we also ask
juries to justify their decisions in terms of either
social values or case facts and law. Besides fur-
nishing a manipulation of the jury’s goal, the
justification requirement has ecological validity;
written justification is a requirement in some
jury systems (e.g. Spain). The study reported
here thus varies jury factions (trained, lay), type
of case being decided ( judgmental or intellec-
tive), and focus of the jury’s justification for
their decision (values or facts). It is expected
that trained jurors will use more normative
influence than lay jurors, with the reverse for
informational influence. Trained jurors are
expected to be more effective in producing
change from pre-deliberation to post-delibera-
tion judgments, but more so in one type of case,
and given one type of justification. If the locus
of power of trained jurors is in their expertise,
their greater influence will be found in intellec-
tive cases, and where justification is based on
facts and law. But if the locus of trained jurors’
power is in their social status or legitimate
power, their influence will be evidenced more
in a judgmental case, and where the decision
must be justified by social values.

Method

Participants and design

Sixteen five-person juries of mixed gender
served in the experiment. The design dictated
that each jury contain trained (n

2) and lay

(n

3) factions. The lay factions consisted of

undergraduate students recruited from an
introductory psychology course in a large
American midwestern state university, who
received course credit for participation (24
men and 24 women, average age

18.6 years).

The trained members of each jury were gradu-
ate students in psychology and law students
(four men and four women, average age

24.6

years). To mimic the situation in real mixed
jury court settings, each trained juror served on
multiple (four) juries, though no two trained
jurors were paired more than once. Lay jurors
each served on one jury. Assignment of trained
jurors was controlled so that each appeared in
an equal number of juries in each of the justifi-
cation conditions. Because the type of case
(intellective vs. judgmental) was varied within
juries (i.e. each jury considered two cases, one
of each type), trained participants were jurors
for the same number of case types and justifica-
tion instructions. Coupled with the fact that no
two trained jurors served together more than
once, this assured that any idiosyncratic influ-
ence of a particular person would not affect the
pattern of findings with respect to the inde-
pendent variables.

In addition to their more advanced age and

education, trained jurors were distinguished by
having been trained in the procedures of the
university Student Judicial Office (SJO). They
attended training sessions routinely given by
the SJO for officers who try student infraction
cases, and were instructed in the rules and pro-
cedures of the students code and SJO trials.

Each jury judged two cases, one of which pre-

sented a relatively judgmental, the other a rela-
tively intellective issue (see the description of
pilot work below). Moreover, juries were asked
to justify their final group decision in writing;
half the juries were told that the justification
could refer only to law and case facts, whereas
the remainder were told they could refer to
social values in addition to law and facts. Thus
the design consisted of factions within juries (lay
vs. trained), type of case being decided ( judg-
mental vs. intellective, to be decided by each
jury), and type of justification required (law and
facts only vs. law, facts, and social values).

Kaplan & Martin

mixed groups

351

Procedure

Lay jurors were recruited for a study putatively
evaluating the student judicial process. Each
convened jury was told that the university was
considering changes to the judicial process to
bring it closer in practice to the United States
court system, that is, to change from a system
where infractions of the student code are tried
by officials of the SJO to one where the
decisions are predominantly made by peers of
the accused, together with SJO officers.
Credibility of this cover story and acquaintance
with the SJO system were enhanced by the fact
that stories about SJO cases and activities
appear regularly in the student newspaper. The
trained jurors were introduced as the members
of the jury from the SJO, and lay jurors were
informed that they were graduate students or
law students who had been trained by the SJO,
and were serving in multiple trials. Jurors were
told that they would be trying actual cases that
had already been heard by the SJO (though not
by the trained members of their juries) so that
we could compare their outcomes and pro-
cesses with those of the SJO panels to evaluate
the viability of changing the system. Trained
members were also told that they were engaging
in an evaluation of a new process in the justice
system, but they were paid US $40 for their par-
ticipation in the four trial sessions. The setting
was conceptually similar to that of mixed juries
in that inexperienced jurors were paired with
experts who regularly and repeatedly tried
cases, and who bore the imprimatur of the
court system.

Each jury decided two cases of infractions of

the Student Judicial Code, in counterbalanced
order across the eight juries within each justifi-
cation condition. One was written to invoke a
judgmental or value issue (e.g. harassment).
That is, the question raised was not whether cer-
tain acts had been committed by the accused,
but whether these constituted violations of
legally and socially prescribed rules. The other
case involved commission of proscribed acts,
such as destruction of property or falsification
of records, which involved a question of
whether certain events did or did not occur,
and whether they had been committed by the

accused. The issue in these intellective or fac-
tual cases was not whether something was right
or wrong, but whether facts showed that it had
happened and whether the accused was the cul-
prit. To enhance generalizability, and to insure
that no trained juror was exposed to the same
case in his or her multiple appearances, eight
replications of cases of each case type were
used, each jury judging one case replication of
each type (see the following section on case
materials).

For each case, juries were first given the rel-

evant judicial code (in writing) and a written
summary of the charge and the evidence; this is
the same process that is used by the SJO. The
summary contained testimony from an SJO
investigator based on sworn interviews with wit-
nesses, and a rebuttal from the accused. After
privately reaching individual verdicts, confi-
dence in the verdict (0–10 scale) and punish-
ment recommendation (chosen from a list of
11 options, graded in severity), juries deliber-
ated to unanimity on the same three judgments.
To lend credibility to the punishment recom-
mendation task, participants were asked to rec-
ommend a punishment even if they voted ‘not
guilty’ because the verdicts would be reviewed
by the SJO and compared to SJO decisions,
which couldn’t be known by the present juries.
In addition to the group consensus on verdict
and confidence level, jurors also individually
recorded their private verdict and confidence
after public consensus was reached. They then
were told that the SJO would be reviewing the
decisions, so that they would have to decide on
a justification for the jury decision. Half the
juries were told that the justification must be
based solely on the relevant law and the case
facts. The remaining juries were told that the
justification could appeal to law, facts, and
social values. The same procedure was then fol-
lowed for the second case. Deliberations were
both videotaped and audiotaped to optimize
later coding of content.

Following each decision and justification, a

questionnaire was administered to each juror to
measure subjective reactions to the process and
outcome of the decision making. The 15 ques-
tions dealt with satisfaction with the decisions

Group Processes & Intergroup Relations 2(4)

352

and deliberation, perceived influence by self
and others, degree of participation by self and
others, perceived tension and pressure, and
breadth of facts that were discussed.

After the last set of subjective reactions was

obtained, the trained jurors were dismissed and
the lay jurors were debriefed. Trained jurors
were not debriefed until after all experimental
sessions were completed.

Construction of the case materials

Sixteen cases were used in the experiment, eight
of which were judgmental and eight of which
were intellective. These were based on actual
cases from the SJO files, but were modified in
several stages to produce cases that met study cri-
teria. Sixteen cases were selected from the files
so that half were expected to present predomi-
nantly factual issues (e.g. theft, property destruc-
tion) and half, value issues (e.g. harassment,
hazing). Where necessary, case evidence was
revised to (a) present a mixed appearance of
guilt, and (b) assure that the prime issues in each
case reflected the prescribed value or factual
basis. Cases were reproduced on official SJO evi-
dence forms, and witness, defendant, and plain-
tiff names were blocked out to enhance the
appearance of realism. The cases were pre-
sented to pilot participants in a preliminary
session (n

24). Participants were first asked to

evaluate each case for guilt or innocence, and
for their confidence in the verdict (on a scale of
1–10), and then to judge whether the deciding
issue in each case was one of value or of fact
(dichotomous choice). For the latter judgment,
definitions of value and fact issues consistent
with Laughlin and Ellis (1986) were provided
(available from the first author). After the first
session, cases were revised on the basis of partic-
ipant comments so that they would be roughly
equivalent in guilt appearance, and would pres-
ent either value or factual issues. Revised cases
that most closely met these criteria were pre-
sented to participants (n

36) in the second

session. The two types of cases were roughly
equivalent in guilt appearance, that is, multiply-
ing confidence by

1 for a not guilty verdict, and

1 for a guilty verdict, and adding a constant of
10 yielded average verdict-confidence scores of

13.40 and 14.61 for factual and judgmental
cases, respectively (where the scale midpoint was
10). Thus, the two sets of cases were roughly
equivalent, and presented a mild appearance of
guilt, which would allow room for change after
discussion. In addition, 75 percent of the pilot
participants, when given formal definitions of
judgmental- and intellective-typed issues, ident-
ified the judgmental cases as predominantly
involving value issues, and 75 percent, on aver-
age, identified the cases we classified as factual
as, indeed, predominantly involving factual
issues. Examples of judgmental cases included
in the final set of cases included involuntary
hazing via taking the victims clothes while he was
in a shower so that he had to run naked through
a coed dorm, and unwanted sexual advances by
an acquaintance in a woman’s dorm room late at
night. Examples of intellective cases included
tearing pages from a book in the library and fal-
sifying one’s course grades by gaining access to a
university computer. The full case materials may
be obtained from the first author.

Another pilot study was conducted to quanti-

tatively order the penalties within SJO jurisdic-
tion. Eleven penalties (ranging from ‘letter of
reprimand’ to ‘expulsion from the university’)
were presented to pilot participants (n

30)

along with formal definitions of the categories
of offenses to which the four experimental cases
belonged (i.e. ‘Harassment’, and ‘Damage,
destruction, or defacement of property’). Given
the charges (note that these participants were
not given the experimental cases), participants
were asked to rate the severity of each penalty
for defendants found guilty of the target charges
(scale ranging from 1–10). Each penalty was
then assigned a severity value, corresponding to
its ordinal position in the severity ratings, that is,
from 1–11. For example, the penalty of ‘proba-
tion’, being the fourth most severe penalty, was
assigned a severity value of ‘8’.

Results

Verdict-confidence

The purpose of this experiment was to compare
the relative influence of lay and trained jurors
on the group decision. Simple expressions of

Kaplan & Martin

mixed groups

353

guilt or innocence were not sensitive to the
effects of variations in type of case or imposed
justification on juror factions; all juries judging
the judgmental cases eventually found for guilt,
while half the factual cases resulted in guilty ver-
dicts. Given that there was little room for move-
ment in the former cases, it is not surprising
that analysis of the dichotomous verdicts pro-
duced no differences due to the independent
variables. Consequently, all tests of the hypothe-
ses were performed on the verdict-confidence
continuous scores, which provided the poten-
tial for more sensitive tests of the independent
variables. Because our interest was in the rela-
tive contribution of lay and trained factions to
judgment of the cases, the quantitative measure
of verdict-confidence appeared to be most
plausible. Verdict-confidence scores were com-
puted for each juror both before and after
deliberation by multiplying the confidence
rating (1–10) by

1 for a not-guilty verdict, and

1 for a guilty verdict, and then adding 10 to
the product to yield a positive score, which
ranged from 0 (certain of innocence) to 20
(certain of guilt).

Verdict-confidence was examined as a func-

tion of type of justification, type of issue, and
whether the verdict preceded or followed dis-
cussion (ignoring factions for the moment),
with repeated measures on the latter two fac-
tors. The verdict-confidence score following dis-
cussion was each group’s consensus decision.
The only significant findings were an effect for
type of issue and an interaction between type of
issue and timing of the judgment (see Table 1).
Judgmental issues led to greater confidence in
guilt both before and after discussion (F(1, 14)

12.18, p .01), likely reflecting character-
istics of the particular cases selected. More
interesting, the data show a polarization effect,
whereby discussion increased doubt in the fac-
tual cases, which had elicited lower scores of
verdict-confidence at the outset, but enhanced
certainty in judgmental cases, which had pro-
duced stronger initial certainty (F(1, 14)

29.85, p

.01).

The critical concern was with the relative

impact of lay and trained factions. This was
assessed in two ways. First, verdict-confidence
scores were computed for each jury faction, and
faction was added as a between-subjects factor
to the analysis of type of issue, type of justifica-
tion, and time of the judgment (before vs. after
discussion). Because the interest was in judg-
ments within factions, the postdiscussion scores
that were analyzed were the within-faction aver-
ages of the individual, private responses that
were obtained after the group consensus was
reached. Interactions between type of issue and
time of judgment (F(1, 14)

27.09, p .01),

and between juror faction and type of issue
(F(1, 14)

12.35, p .01) were superseded by

a three-way interaction between type of issue,
time of judgment, and juror faction (F(1, 14)

15.57, p

.01). Simple effects tests of this inter-

action disclosed that in both types of cases,
trained jurors did not change their judgments
after discussion, whereas lay jurors changed
their judgments in the direction of trained
jurors’ initial judgments after discussion, more
so in the judgmental case (see Table 2). For
purposes of comparison, Table 2 includes the
group consensus verdict-confidence decisions;
note that the final group decisions were closer

Group Processes & Intergroup Relations 2(4)

354

Table 1. Confidence in guilt for intellective and judgmental cases before and after deliberation (group
consensus)

Type of issue

Intellective

Judgmental

Mean

SD

Mean

SD

Pre-deliberation

12.57

(4.14)

15.32

(2.30)

Post-deliberation

10.50

(5.73)

17.68

(1.20)

Note. Verdict-confidence scale ranged from 0 (certain of innocence) to 20 (certain of guilt). All means differ
at p

.05 in SPSS MANOVA simple effects contrasts.

to the prediscussion verdict-confidence judg-
ments of the trained jurors than to the initial
judgments of the lay jurors.

The second strategy to assess the relative

impact of factions was to calculate correlations
between individual prediscussion verdict-confi-
dence and group consensus verdict-confidence
separately for participants within each faction.
Higher correlations would reflect greater influ-
ence over the final outcome. Comparisons of
factions overall and within the type of issue
and type of justification conditions yielded sev-
eral significant differences between lay and
trained jurors in their influence over the con-
sensus judgment. Generally, trained jurors (r

.83) were considerably more influential over
the consensus judgment than lay jurors (r

.43), (z

4.11, p .01). But the relative advan-

tage of trained jurors shifted with conditions.
Trained and lay jurors were equally effective
when deciding the intellective cases (r

.84

and .94, respectively, z

2.17, ns), or when the

justification permitted only reference to facts
(r

.66 and .86, respectively, z 2.09, ns).

The difference between the factions lay in the
judgmental cases (trained jurors, r

.56, lay

jurors, r

.13, z 3.68, p .01) and when jus-

tification included values (trained jurors, r

.79, lay jurors, r

.27, z 3.33, p .01). Thus,

trained jurors wielded more power over the
final judgment, but only when values were
inherent in the case or were included in the
justification.

Punishment

Individuals before deliberation, and then
groups, were asked to recommend a penalty
from among the SJO choices. The rec-
ommended penalties were assigned a score
(1–11) according to the position of that penalty
in the ordinally graded series of penalties
(Table 3). Analysis was first conducted on pun-
ishment level as a function of type of issue, type
of justification, and time of judgment (before
or after discussion). The punishment score fol-
lowing discussion was each group’s consensus
decision.

The three-way interaction between issue, jus-

tification, and time of punishment recommen-
dation was significant (F(1, 14)

4.41, p .06).

After discussion, participants became less puni-
tive when a factual issue had to be justified by
facts and law, and when a value issue could be
justified by factors additional to facts and law. In
other words, jurors became more lenient when
issue and justification were congruent.

To assess their relative influence, factions

were treated as a factor in the overall analysis,
and postdiscussion punishment scores were the
within-faction averages of the individual, private
responses that were obtained after the group
consensus was reached. Membership in factions
produced no significant effects on punishment.
Parallel to the treatment of verdict-confidence,
correlations between individual prediscussion
and group consensus punishment recommen-
dations were calculated separately for partici-

Kaplan & Martin

mixed groups

355

Table 2. Mean confidence in guilt for jury factions before and after deliberation (individuals within factions)

Intellective case

Judgmental case

Trained

Lay

Group consensus

Trained

Lay

Group
consensus

Pre-deliberation

M

10.85

a,d

14.03

b

16.94

c

14.16

b

SD

(4.41)

(4.73)

(2.48)

(3.58)

Post-deliberation

M

1

9.37

a

11.38

d

(10.50)

17.90

c

17.67

c

(17.68)

SD

(6.11)

(6.26)

(1.34)

(2.58)

Notes. Verdict-confidence scale ranged from 0 (certain of innocence) to 20 (certain of guilt). Group
consensus after deliberation is the verdict-confidence score agreed upon by the entire group; the remaining
entries are the means of individual, private responses by members of the given faction. Means that do not
share subscripts differ at p

.05 in SPSS MANOVA simple effects contrasts.

pants within each faction. Higher correlations
would reflect greater influence over the final
punishment outcome. Comparisons of factions
overall and within the type of issue and type of
justification conditions yielded two significant
differences. The prediscussion preferences of
trained jurors were more influential in deter-
mining the consensus recommendation than
those of lay jurors in the factual cases (r

.78

and .46, respectively, z

2.30, p .05), but the

reverse was true for judgmental cases (r

.31

and .74, respectively, z

2.64, p .01). The

pattern of faction dominance was different for
verdict-confidence and punishment decisions.
Trained jurors exerted more control over ver-
dict-confidence in judgmental cases, but over
punishment in factual cases. In punishment
decisions for judgmental cases, in fact, it was the
initial preferences of lay jurors that most deter-
mined the group consensus.

Discussion content

Each complete statement made by a participant
during discussion was coded for normative or
for informational influence content. A state-
ment or utterance was coded if it was judged a
complete thought (which could include assent
or dissent with another’s thought), and a state-
ment that continued after an interruption was
considered as a single statement if it continued
the same line of thought. If a statement
impinged on more than one category, it was
multiply coded. One coder tallied each utter-
ance within 1 (or more, if appropriate) of 10
categories, as follows:

1. Statement about a fact contained in the tes-

timony.

2. Inference from, and elaboration on, testi-

monial facts.

3. Reference to societal or group norms or

values.

4. Reference to personal norms or values.
5. Expression of verdict preference.
6. Expression of punishment preference.
7. Pressure to agree with group decisions.
8. Nonspecific pressure (e.g. ‘hurry up’).
9. Procedural references and references to

legal rules.

10. Other.

In order to establish coder reliability, a

second coder independently coded 8 of the 32
discussions. The two sets of codings were com-
pared for agreement by the formula 2 [number
of

categorical

agreements

within

a

dis-

cussion]/[total number of categorizations for
coder 1

coder 2] (see Kaplan, 1989; Kaplan &

Miller, 1987; and Kelly, Jackson, & Hutson-
Comeaux, 1997, for similar use of this reliability
statistic). The agreement coefficients for the
eight discussions in the reliability sample
ranged from .82 to .93, with a mean of 87.75
percent. To see whether the high coefficients
were due to disproportionate numbers of state-
ments coded into few categories, the statistic was
also applied to intercoder agreement for each
category in each case. Coefficients ranged from
.75 (in an instance of only four entries) to 1.00
in the two categories that constituted the infor-
mational influence score. For the five categories

Group Processes & Intergroup Relations 2(4)

356

Table 3. Mean level of punishment assigned by individual jurors as a function of type of case and type of
justification required

Intellective case

Judgmental case

Justification

Pre-deliberation

Post-deliberation

Pre-deliberation

Post-deliberation

Law and facts

M

(

5.06

(

4.13

(

4.62

(

6.00

SD

(1.96)

(3.36)

(1.55)

(2.88)

Any justification

M

(

5.70

(

6.25

(

4.08

(

3.38

SD

(1.53)

(3.73)

(1.69)

(3.20)

Note. Assigned punishments fell on a graded scale, from 1 (least severe) to 11 (most severe).

comprising the normative influence score, most
of the coded utterances fell into the verdict pref-
erences category, with the coefficients ranging
from .94 to .98 for the four cases. Combining
over the remaining four normative categories
yielded coefficients ranging from .60 to 1.00.

An informational influence content score was

derived by combining the number of state-
ments about testimonial facts, inferences and
elaborations (categories 1 and 2). Normative
influence was indexed by combining references
to societal, group, and personal norms and
values, and references to verdict and punish-
ment preferences (categories 3–7). The coding
scheme was originally segmented for direct
assertions versus questions within each cat-
egory, but because the patterns in both factions
were similar for assertions and questions, they
were combined. Number of statements of each
sort, informational and normative, were
summed for each faction within each jury.
Separate counts were made for the segments of
the discussion dealing with verdict and confi-
dence, punishment, and justification. For each
discussion segment, the number of statements
made were analyzed as a function of type of
statement (normative or informational), type of
issue (factual or judgmental), type of justifica-
tion (fact and law or any justification), and jury
faction (trained or lay).

Significant effects on number of statements

were found only in the discussion segment per-
taining to verdict and confidence, which makes
sense in that this segment constituted the bulk
of the time spent in discussion. First, there was
an interaction between type of statement and
type of issue (F(1, 14)

11.98, p .01), such

that discussion was more informational (M

31.53) than normative (M

22.13) in the fac-

tual cases, whereas the number of informa-
tional (M

17.44) and normative (M 18.18)

statements did not differ in the judgmental
cases. This accords with findings that the rela-
tive predominance of normative or informa-
tional influence is a function of the type of issue
being discussed (see, e.g. Kaplan, 1989; Kaplan
et al., 1994).

Turning to faction differences, there were two

interactions. First, faction and type of issue inter-

acted (F(1, 14)

6.89, p .02); trained (M

18.09) and lay (M

17.53) factions, taken as

wholes, produced similar numbers of statements
in juries deciding the judgmental cases, but lay
factions (M

31.09) produced more statements

than trained factions (M

22.56) when dis-

cussing the factual cases. The ratio of lay to
trained jurors in each group was 3:2, so another
way of viewing the verbal output of factions is
that individual members of trained and lay fac-
tions were equally active in discussing the factual
cases (Ms

11.28 and 10.36, respectively), but

trained jurors were individually more active in
discussing the judgmental cases (Ms

8.77 and

6.03, respectively). An analysis based on mean
numbers of statements per participant within
factions disclosed the expected faction by type
of issue effect (F(1,14)

8.82, p .01). Recall

that it was in the judgmental, but not the factual
cases, that trained jurors exerted more influ-
ence on the group decision. Thus, the greater
influence of trained jurors was related, at least in
part, to their increased activity, relative to lay
jurors, in judgmental cases. The other side of
the coin is that lay jurors were able to withstand
the influence of trained jurors in the factual
cases, where they took an equally active role.

Second, there was an interaction between fac-

tion and type of influence (F(1, 14)

11.91,

p

.01. It had been expected that trained

jurors, being a power majority, would wield
more normative influence than lay jurors. But
trained (M

19.97) and lay (M 20.34) fac-

tions, taken as a whole, did not differ in number
of normative statements. Instead, they differed
in informational output, lay jurors producing
more informational statements (M

28.28)

than trained jurors (M

20.68). But when

taking into account the number of jurors within
factions, that is, in analyzing the number of nor-
mative and informational statements per
trained and lay juror, trained jurors (M

9.94)

individually produced more normative state-
ments than lay jurors (M

6.78), whereas the

individual production of informational state-
ments did not differ for trained (M

10.34)

and lay (M

9.43) jurors (Interaction F(1,14)

14.55, p .005).

In summary, trained individuals were more

Kaplan & Martin

mixed groups

357

normative in their influence, and lay and
trained individuals were equally informational.
Intellective-type cases invite more informational
than normative influence, and it was in this type
of case that lay jurors were the equal of trained
jurors in discussion activity, and, not coinciden-
tally, were equal to trained jurors in influencing
the verdict. Lay jurors were also equal to trained
jurors in using informational influence, and
were consequently at less of a disadvantage in
cases that are more amenable to informational
(intellective) solution. In the judgmental cases
in which trained jurors were more influential,
they were more active than lay jurors, and were
more likely to use the form of influence – nor-
mative – that is most effective in such cases.

Post-decisional reactions

After the jury decided verdict, confidence, pun-
ishment, and justification in each case, mem-
bers individually completed a questionnaire
dealing with satisfaction, perceived influence,
degree of participation, tension and pressure,
and breadth of discussion. Responses on scalar
items could range from 1 to 10, with higher
ratings reflecting higher levels of the particular
dimension (e.g. satisfaction with the verdict).
Responses to each item were analyzed as a func-
tion of faction, type of case, and type of
required justification.

Regardless of faction and justification, par-

ticipants were more satisfied with the verdict in
the judgmental (M

8.62) than in the intellec-

tive (M

7.69) case (F(1, 14) 7.39, p .05).

Similarly, participants were more satisfied with
punishments meted out for judgmental (M

8.97) than for intellective (M

8.14) cases (F

(1, 14)

5.73, p .05). On the whole, partici-

pants were rather satisfied with both verdict and
punishment group decisions.

Lay group members believed more strongly

than trained members that all group members
participated fully in discussion when the issue
was judgmental and justification could be broad
in content (M

8.95 and 7.50, respectively),

three-way interaction (F(1, 14)

5.94, p .05).

Recall that in this condition juror factions were
not equally active, trained jurors being more
active as individuals than lay jurors, so that it

could be argued that trained jurors more accu-
rately perceived the unequal contribution of
factions to discussion.

Trained jurors were also more sensitive to

their greater influence, believing that, as indi-
viduals, they had more influence over decisions
(M

6.38) than lay jurors thought they (i.e. the

lay jurors) had (M

5.40) (F(1, 14) 13.55,

p

.005). However, neither faction recognized

that the differential influence of factions was
contingent on the type of case being decided.

Participants were also asked to select from

among all group members the person who par-
ticipated most, and the person who participated
least, in the discussion, with an option for every-
one participated equally. Lay jurors overwhelm-
ingly thought that trained jurors participated
the most (59% of selections) but trained jurors
modestly concluded that one of their number
participated the most in 25 percent of their
selections, reporting more often (65% of selec-
tions) that everyone participated equally. The
difference between the proportions of lay and
trained juror nominations of the latter as most
active was significant (z

2.94, p .01).

No other effects reached significance for the

post-decisional reactions. To summarize, par-
ticipants were generally satisfied with discussion
and outcome, but differed in perceptions of
participation and influence. Trained members
were more aware of their greater participation,
but were not sensitive to variations due to case
type. Nor were participants aware of the role of
case type in differential influence, all partici-
pants believing that trained jurors were more
influential despite their smaller numbers.
Finally, neither faction reported more (or less)
tension and pressure than the other. In view of
the findings with respect to actual influence
and participation, status effects appear to be
subtle; while status affected the extent of influ-
ence, participants were aware of their own influ-
ence and relative rate of participation in only
the most general way.

Discussion

The mixed jury

Three questions were posed concerning juries

Group Processes & Intergroup Relations 2(4)

358

composed of trained and lay members. Do
trained and lay factions differ in their impact on
the jury decisions? Do the factions use different
means of influence during deliberation, i.e. do
they differ in influence process? And, do differ-
ences in impact and influence process depend
on the type of case being decided? According to
our review of the literature, it was expected that
the relative influence of trained and lay factions
would vary with the type of case being decided,
but the direction this difference should take
was unclear. It was also expected that, com-
pared to the opposite faction, lay jurors would
avail themselves more of informational forms of
influence whereas trained jurors would use nor-
mative influence more. Moreover, given their
propensity for information influence, lay jurors
might be expected to be more active in intel-
lective cases, which lend themselves more to
intellective arguments. The results generally
accorded with expectations: relative impact of
the factions depended on the type of issue
being decided, and factions differed both in the
means of attempted influence, and in their rela-
tive activity in the different types of cases.

Trained jurors had impact on consensus ver-

dicts and confidence more than did lay jurors
when the issue was judgmental, and the
required justification could include appeal to
values. On the other hand, factions were
equally influential in affecting outcome when
the issue was intellective or when the justifica-
tion was limited to factual and legal argument.
Influence on private judgments followed a simi-
lar pattern in that lay jurors generally changed
their judgments more, but to a greater extent in
the judgmental case. Finding greater change
for both public and private confidence in guilt
suggests that the influence of the trained over
the lay jurors in judgmental cases was not
limited to inducing mere compliance with the
power majority, but extended to personal judg-
ments of guilt.

In initially discussing the potential advantage

of trained over lay factions, it was unclear
whether the former would be more effective
because of their expert or legitimate power,
that is, whether lay jurors are responding to
their expertise in the law and the system, or to

their social status. The pattern of influence sug-
gests that it is the legitimate power of the
trained jurors to prescribe social norms that was
the basis of their greater influence. It was in
those instances where social values were the
focus that the trained factions exerted their
greatest influence; had their advantage been in
their expertise in the legal system, they would
have been most influential where facts had to
be related to the law, and social values were of
secondary, if any, importance. In European
mixed juries, where status differences are
marked, this could indeed prove a great advan-
tage for judges in cases that invoke social values.

Punishment decisions appeared to present a

different pattern. Factions did not differ in
influence on private decisions, but trained
jurors were more influential for group consen-
sus in the intellective cases, whereas lay jurors
were more influential in the judgmental cases.
Why the apparent reversal of influence patterns
from verdict to punishment consensus
decisions? To offer a speculation, unlike judg-
ments about guilt or innocence, punishment
more likely involves moral retribution, that is,
the convicted party must answer to the com-
munity for his/her acts. Where moral retribu-
tion is concerned, laypersons may possess
legitimate status as representatives of the com-
munity that has been wronged, and therefore,
in punishment decisions, unlike verdicts,
laypersons are not of weaker status. Thus, the
power wielded by the trained faction in verdicts
may be legitimate power, conferred by their
status as arbiters of social norms regarding what
is permissible. This superiority vanishes in pun-
ishment decisions, where laypersons possess
legitimate status as well. Endowed with legiti-
mate power, lay jurors would not only match
the influence of trained jurors in punishment
decisions, but would exceed their influence in
judgmental cases. Future research should
directly vary, or at the least assess, self-percep-
tions of juror factions along with the types of
issues raised by the decision tasks to see whether
perceptions of source of power will shift with
the decision (verdict or punishment) and the
case issue (intellective or judgmental).

The process of influence during discussion

Kaplan & Martin

mixed groups

359

accords with the patterns of faction influence
noted above. As individuals, trained jurors were
more active than lay jurors in the judgmental
cases, but the members of the two factions were
equally active in the intellective case dis-
cussions. Recall that the trained jurors influ-
enced the consensus decisions more in
judgmental cases, whereas faction influence was
about equal in intellective cases. Looking at the
form of influence that was exerted, lay jurors
were equal to trained jurors in informational
influence. Informational influence would be
more effective in cases that evoke intellective
issues (Rugs & Kaplan, 1993), so that it follows
that lay jurors would offset the social power of
trained jurors in deciding such cases or if asked
to limit justification to facts. In short, anything
that focuses concern on factual matters
improves the influence of group members who
argue informationally. Similarly, anything that
focuses concern on evaluative matters favors the
influence of members who argue normatively.
In the judgmental cases, trained jurors argued
more from a normative basis than lay jurors,
which accords with their greater influence in
such cases.

The presence of a nonunanimity rule in

European juries fosters early agreement, sup-
presses dissent and conflict, and reduces con-
sideration of all possible viewpoints (Nemeth,
1985). Nonunanimous rules reduce evidence
diversity because judge factions are themselves
less diverse, and less likely to entertain diversity
from lay jurors. Fostering thought divergence is
a major contribution of minorities (Nemeth,
1986), but may be blunted by the decision rule.

Another advantage for judges is that they

often have access to case information prior to
trial (Diamond, 1988), which, along with their
experience and social status, engenders greater
confidence, thereby enhancing their influence
(Sev’er, 1989).

Prior studies have demonstrated that lay

jurors in existing courts attribute more status
(Nemeth, 1985) and expertise (Brandstatter et
al., 1984) to trained jurors, who are, in turn,
more influential (Casper & Zeisel, 1972)
though they do not speak to the nature of the
cases being decided or the sources of power.

This study extends prior knowledge in several
ways. By using a more controlled and systematic
laboratory methodology, we presented cases
which, while maintaining realism and involve-
ment in our jurors, varied in their intellec-
tive/judgmental focus. This disclosed that
trained jurors are more influential largely with
cases involving judgmental issues, in which
their influence extended to private judgments
as well as public votes. Coupled with the finding
of equal influence in intellective cases, this
suggested that the source of their influence was
social, rather than expert power. We also
looked past the relative impact of factions to the
dynamics of deliberation and influence modes,
and found that trained jurors were more active
in discussing judgmental cases, and more prone
to using normative influence, dynamics which
would increase their relative influence in judg-
mental type cases. More importantly for the
question of equalizing faction influence, lay
jurors were as active as trained jurors in intel-
lective cases, and engaged equally in informa-
tional influence, thereby increasing their
relative influence in the intellective cases.

Mixed groups

We found that the higher status faction was
more influential than the lower status faction in
a judgmental task, but not in an intellective
task, supporting Kirchler and Davis’ (1986)
conclusion that status is relevant when a task
fosters a ‘power wins’ strategy, but not when a
‘truth wins’ strategy is invoked. This may be
termed an instrumental basis of faction influ-
ence; low status members may possess infor-
mation that is useful for intellective-type
solutions, and their contributions may be valu-
able. In judgmental tasks, which possess a value
component, high status is a marker for the
norms that are instrumental for resolution.
Another basis of differential impact of low and
high status members may lie in their different
discussion styles. Low status members used
informational more than normative influence,
and were more active in the intellective than
the judgmental task discussion. Because intel-
lective tasks naturally invoke more informa-
tional influence (Kaplan & Miller, 1987) and

Group Processes & Intergroup Relations 2(4)

360

are more susceptible to informational influence
(Rugs & Kaplan, 1993), the greater tendency of
low status members toward informational influ-
ence increased their impact. Thus, in addition
to their instrumentality for solutions to intellec-
tive issues, low status members are also likely to
engage in discussion processes that enhance
their effectiveness in such issues. Note that the
key to differential influence is not limited to
whether the issue is intellective or judgmental,
but more generally to whether the group
focuses on a factually correct or a value-satisfy-
ing solution. For example, the same patterns of
relative influence were found when juries had
to justify their verdicts by facts and law versus
facts, law, and values.

Note that the social majority in this study was

a numerical minority at the outset, though no
effort was made to control their initial
responses so that they would be a clear numeri-
cal minority with regard to initial judgment.
Thus, any conclusions with regard to numeri-
cally determined factions would be tentative.
However, patterns of differential impact due to
social status closely parallel those reported for
both power and numerical minorities and
majorities. Like low status members, minorities
are more likely to engage in informational than
normative influence (Wood et al., 1994). Thus,
whether the factions differ in social status or in
numerical minority/majority status, the conclu-
sion may be the same (Perez, Papastamou, &
Mugny, 1995). When the focus is on demon-
strably correct judgments, as in intellective,
problem solving, and ‘truth wins’ tasks, or when
the group is required to justify its decision by
facts, status differences have less influence on
the outcome, that is, the information provided
by low status or minority members is important.
When the focus is on values and preferences, as
in judgmental or social reality tasks, or when
the group is required to justify its decision by
values, status becomes more relevant, and the
normative pressure of opinion majorities is
important to resolution.

One more finding is worth discussion.

Particularly in the judgmental cases, in which
their normative power should be most relevant,
the trained faction influenced the judgments of

lay members on both public and private
measures. That is, on an issue that is most
amenable to normative argument, the high
status faction effected both public and private
change. This accords with findings in which
majorities induced both compliance and atti-
tude change (Baker & Petty, 1994; Mackie,
1987). De Vries, De Dreu, Gordijn, and
Schuurman (1996) interpret the ability of
majorities to produce private change as evi-
dence that majorities, and not minorities, moti-
vate the group to engage in careful, systematic
processing specific to the message.
Unfortunately, there is no direct evidence of
depth of processing by group factions in the
present study, so their conclusion cannot be
definitively evaluated.

Reducing the effect of status

It is reasonable to expect that initial factions
based on lay or judge membership will persist
over the course of deliberation. Within factions,
there should be a sense of shared social identi-
fication due to mutually common status. Shared
identity increases the likelihood that factions
will coalesce (Sachdev & Bourhis, 1991).
Moreover, strong identity ties will increase
resistance to persuasion as a means of main-
taining subgroup identity, for example, a fac-
tion that is uniform in preferences will be more
resistant (Nemeth, 1986). Due to their common
background and experience, not to mention
continual working associations, judges have
more in common, that is, more of a shared
identity, and are therefore more likely to
remain cohesive and resist persuasion. Put
another way, the judges have less chance of
losing support through defection because of
their more homogeneous sense of shared ident-
ity. And, the more cohesion in a group, the
greater its ability to influence its members and
resist influence (Latane & Wolf, 1981).

Remediating the differential power of lay and

judge factions is important in light of the con-
ditions that naturally favor the latter. We have
seen that decision tasks that center on intellec-
tive issues can equalize influence, but in the
real world courts cannot be so selective in the
sorts of cases being tried, and their substantive

Kaplan & Martin

mixed groups

361

issues. More likely strategies follow from con-
sideration of the roles and expectations of
group members. Lay jurors may believe that the
role of judges in their midst is to provide direc-
tion, that is, the proper role of officers of the
court is to dominate the discussion and the
decision. But, when people of different social
roles are given equal task roles, they will be simi-
larly influential (Eagly, 1987). If jurors are
induced to adopt roles that are equally instru-
mental to the decision, influence may be equal-
ized. Lay jurors could be instructed in the
relevant law, assured that their role is to deter-
mine the truth of facts and their application to
the law, and most relevant for their role, told
that their importance to the jury is to serve as a
conduit of community values.

The last point merits expansion. Recall that

lay jurors were more influential in punishment
decisions in judgmental cases, where their role
of community conscience in meting out pun-
ishment for violation of community standards is
most salient. Power conferred by status in the
group is enhanced when the status is supported
by status external to the group (Ridgeway,
Diekema, & Johnson, 1995). External status
would generally favor the judge faction, but can
be assigned to the lay faction as well by inform-
ing them of the importance of the constituency
they represent for justice.

In addition to the role assigned to judges, lay

jurors may have expectations about the quality
of their performance; status cues associated
with valued groups can lead to expectations of
greater power (Berger, Webster, Ridgeway, &
Rosenholtz, 1986). Research in expectation
states (Cohen, 1982; Molm & Hedley, 1991)
suggests some remedies for the imbalance in
influence due to expectations. First, infor-
mation that contradicts performance expecta-
tions could be provided, such as telling lay
jurors about the fallibility of judges. Second, the
status of lay jurors could be enhanced by telling
them of their role in the judicial process. Third,
lay jurors could be informed that they share
some expertise with the judges in that they are
also ‘expert’ with regard to social norms, and
are equally competent to judge facts and wit-
nesses. Finally, lay jurors could be provided with

other low social status models who are compe-
tent in the jury’s task. This can be done by
informing them of competent decisions made
by other juries, or by insuring that at least one
lay member has had prior jury experience.

It is clear from the foregoing conjecture, and,

more directly, from the results of the study, that
experienced judges, or higher status factions,
need not be disproportionately influential in
group decision making.

Acknowledgements

The research was supported in part by a Fulbright
Fellowship awarded to Ana M. Martin. We thank
Anne Reither and L. Tatiana Wanshula Panas for
their assistance in data collection and analysis,
respectively.

References

Back, K. W., & Davis, K. E. (1965). Some personal

and situational factors relevant to the consistency
and prediction of conforming behavior. Sociometry,
28, 227–240.

Baker, S. M., & Petty, R. E. (1994). Majority and

minority influence: Source position imbalance as a
determinant of message scrutiny. Journal of
Personality and Social Psychology, 67, 5–19.

Berger, J., Webster, M., Jr., Ridgeway, C. L., &

Rosenholtz, S. J. (1986). Status cues, expectations,
and behaviors. In E. Lawler (Ed.), Advances in
group processes (Vol. 3, pp. 1–22). Greenwich, CT:
JAI Press.

Brandstatter, H., Bleckwenn, M., & Kette, G. (1984).

Decision-making of industrial tribunals as
described by professional and lay judges.
International Review of Applied Psychology, 33,
137–159.

Cajal-Blanco, B. (1994). El cambio de verdicto en el

jurado: Influencia de variables psicosociales.
Unpublished doctoral dissertation, Universidad
AutÛnoma de Barcelona.

Casper, J., & Zeisel, H. (1972). Lay judges in the

German criminal courts. Journal of Legal Studies, 1,
135–191.

Chaiken, S., Wood, W., & Eagly, A. H. (1996).

Principles of persuasion. In E. T. Higgins &
A. W. Kruglanski (Eds.), Social psychology:
Handbook of basic principles (pp. 702–742). New
York: Guilford.

Cohen, E. G. (1982). Expectation states and

Group Processes & Intergroup Relations 2(4)

362

interracial interaction in school settings. Annual
Review of Sociology, 8, 209–235.

Deutsch, M., & Gerard, H. (1955). A study of

normative and informational social influences
upon individual judgments. Journal of Abnormal
and Social Psychology, 51, 629–639.

De Vries, N. K., De Dreu, C. K. W., Gordijn, E., &

Schuurman, M. (1996). Majority and minority
influence: A dual role interpretation. In W.
Stroebe & M. Hewstone (Eds.), European review of
social psychology (Vol. 7, pp. 145–172). Chichester:
Wiley.

Diamond, S. (1988). When laypersons set the sentences

in civil courts. Unpublished manuscript, University
of Illinois, Chicago.

Eagly, A. H. (1987) Sex differences in social behavior: A

social-role interpretation. Hillsdale, NJ: Erlbaum.

French, J. R. P., & Raven, B. (1959). The bases of

social power. In D. Cartwright (Ed.), Studies in
social power (pp. 150–167). Ann Arbor, MI:
Institute for Social Research.

Gerbasi, K. C., Zuckerman, M., & Reis, H. T.

(1977). Justice needs a new blindfold: A review of
mock jury research. Psychological Bulletin, 84,
323–345.

Hastie, R., Penrod, S., & Pennington, N. (1983).

Inside the jury. Cambridge, MA: Harvard University
Press.

Insko, C. A., Smith, R. H., Alicke, M. D., Wade, J., &

Taylor, S. (1985). Conformity and group size: The
concern with being right and the concern with
being liked. Personality and Social Psychology Bulletin,
11, 41–50.

Kaplan, M. F. (1989). Task, situational, and personal

determinants of influence processes in group
decision making. In E. J. Lawler & B. Markovsky
(Eds.), Advances in group processes (Vol. 6, pp.
87–105). Greenwich, CT: JAI Press.

Kaplan, M. F., & Martin, A. M. (in press). The

influence of expert vs. non-expert members of
juries: The Spanish jury as an illustration. In S. S.
Nagel (Ed.), Handbook of global legal policy. New
York: Marcel Dekker.

Kaplan, M. F., & Miller, C. E. (1987). Group decision

making and normative vs. informational influence:
Effects of type of issue and decision rule. Journal of
Personality and Social Psychology, 53, 306–313.

Kaplan, M. F., Schaefer, E. G., & Zinkiewicz, L.

(1994). Member preferences for discussion
content in anticipated group decisions: Effects of
type of issue and group interactive goal. Basic and
Applied Social Psychology, 15, 489–508.

Kelly, J. R., Jackson, J. W., & Hutson-Comeaux, S. L.

(1997). The effects of time pressure and task

differences on influence modes and accuracy in
problem-solving groups. Personality and Social
Psychology Bulletin, 23, 10–22.

Kirchler, E., & Davis, J. H. (1986). The influence

of member status differences and task type on
group consensus and member position change.
Journal of Personality and Social Psychology, 51,
83–91.

Latane, B., & Wolf, S. (1981). The social impact of

minorities and majorities. Psychological Review, 88,
438–453.

Laughlin, P., & Ellis, A. (1986). Demonstrability and

social combination processes on mathematical
intellective tasks. Journal of Experimental Social
Psychology, 22, 177–189.

Maass, A., & Clark, R. D., III (1983). Internalization

vs. compliance: Differential processes underlying
minority influence and conformity. European
Journal of Social Psychology, 13, 197–215.

Mackie, D. M. (1987). Systematic and nonsystematic

processing of majority and minority persuasive
communications. Journal of Personality and Social
Psychology, 53, 41–52.

Molm, A. D., & Hedley, M. (1991). Gender, power,

and social exchange. In C. L. Ridgeway & D.
Diekema (Eds.), Gender, interaction, and inequality
(pp. 157–180). New York: Springer-Verlag.

Moscovici, S. (1985). Social influence and

conformity. In G. Lindzey & E. Aronson (Eds.),
The handbook of social psychology (Vol. 2, 3rd ed.,
pp. 347–426). New York: Random House.

Munday, R. (1993). Jury trial, continental style. Legal

Studies, 13, 205–224.

Nemeth, C. J. (1985). Procesos de grupo y de jurado:

Estados Unidos y Francia. In S. Moscovici (Ed.),
Psicología social (Vol. 2, pp. 279–305). Barcelona:
Paidos. (Original work published in 1984)

Nemeth, C. J. (1986). Differential contributions of

majority and minority influence. Psychological
Review, 93, 23–32.

Nemeth, C., & Wachtler, J. (1974). Creating the

perceptions of consistency and confidence: A
necessary condition for minority influence.
Sociometry, 37, 529–540.

Palmer, A. (1988). El jurado y la psicología social.

Barcelona: PPU.

Perez, J. A., Papastamou, S., & Mugny, G. (1995).

‘Zeitgeist’ and minority influence – where is the
casualty: A comment on Clark (1990). European
Journal of Social Psychology, 27, 703–710.

Ridgeway, C. L., Berger, J., & Smith, L. (1985).

Nonverbal cues and status: An expectation states
approach. American Journal of Sociology, 90,
955–978.

Kaplan & Martin

mixed groups

363

Ridgeway, C. L., Diekema, D., & Johnson, C. (1995).

Legitimacy, compliance, and gender in peer
groups. Social Psychology Quarterly, 58, 298–311.

Rugs, D., & Kaplan, M. F. (1993). Effectiveness of

informational and normative influences in group
decision making depends on group interactive
goal. British Journal of Social Psychology, 32,
147–158.

Sachdev, I., & Bourhis, R. Y. (1991). Power and

status differentials in minority and majority group
relations. European Journal of Social Psychology, 21,
1–24.

Sampson, E. E. (1969). Studies in status congruence.

In L. Berkowitz (Ed.), Advances in experimental
social psychology (Vol. 4, pp. 225–270). New York:
Academic Press.

Se’ver, A. (1989). Simultaneous effects of status and

task cues. Social Psychology Quarterly, 52, 327–335.

Skvoretz, J. (1988). Models of participation in status-

differentiated groups. Social Psychology Quarterly,
51, 43–57.

Strodtbeck, F., James, R., & Hawkins, C. (1957).

Sociological status in jury deliberation. American
Sociological Review, 22, 713–719.

Wilke, H. (1996). Status congruence in small groups.

In E. Witte & J. H. Davis (Eds.), Understanding
group behavior (Vol. 2, pp. 67–91). Mahwah, NJ:
Erlbaum.

Wood, W., Lundgren, S., Ouelette, J. A., Busceme,

S., & Blackstone, T. (1994). Minority influence: A
meta-analytic review of social influence processes.
Psychological Bulletin, 115, 323–345.

Paper received 17 September 1998; revised version accepted

19 April 1999.

Biographical Notes

martin f. kaplan is Distinguished Research

Professor at Northern Illinois University. He
obtained his PhD from the University of Iowa in
1965 and has been at Northern Illinois
University since then. He has been a Visiting
Research Professor at the University of California
at San Diego, the University of North Carolina at
Chapel Hill, the University of Melbourne
(Australia), La Trobe University (Australia), and
Leiden University, the Netherlands. His research
interests include group decision processes, jury
decision making, and individual social judgment
processes.

ana m. martin is Associate Professor at the

University of La Laguna (Spain) since 1991. She
obtained her PhD from the University of La
Laguna in 1986. She was granted by the Spanish
Administration as pre- and post-doctoral
researcher from 1985 to 1989 and has been at the
University de La Laguna since then. She was a
Fulbright visiting scholar at Northern Illinois
University for a year from September 1987. At
present she is Departmental Coordinator of
Psychology at her university for the Socrates
Program of Faculty and student exchange among
European Universities. Her research interest
include jury decision making, social perception of
crime and evaluation of rehabilitation programs.

Group Processes & Intergroup Relations 2(4)

364