Organized Interests and Agenda Setting in theU.S. Supreme Court Revisited∗

Gregory A. Caldeira John R. Wright Christopher Zorn†

Ohio State University Ohio State University Pennsylvania State Universitycaldeira.1@osu.edu wright.569@osu.edu zorn@psu.edu

February 18, 2012

∗Prepared for presentation at the Second Annual Conference on Institutions and Lawmaking,Emory University, February 24-25, 2012, Atlanta, GA.†Gregory Caldeira is Distinguished University Professor, Ann and Darrell Dreher Chair in Po-

litical Communication and Policy Thinking, and Professor of Law at Ohio State University. JackWright is Professor of Political Science at Ohio State University. Christopher Zorn is Liberal ArtsResearch Professor of Political Science and Affiliate Professor of Law, Pennsylvania State Univer-sity. The authors thank Alex Cross for making his 2007 Term certiorari data available for analysis.This is a very preliminary draft; comments and suggestions are welcome, but please do not citewithout permission of the authors.

Introduction

Since 1925, the vast majority of the U.S. Supreme Court’s business has come to the Court

through the certiorari (colloquially, “cert”) process. Petitions for a writ of certiorari are

granted at the discretion of the Court, and require the vote of at least four justices to be

granted. The Court denies far more cases than it grants; in recent years, estimates of the

Court’s grant rate for paid petitions has hovered between one and two percent. Since the

effect of a denial of certiorari is to leave the lower court decision standing, the certiorari

decision itself often represents the “final word” in cases eligible for Supreme Court review.

Not surprisingly, for more than five decades scholars have studied the process by which

the justices decide whether to grant or deny petitions for certiorari. Early work emphasized

the influence of procedural and jurisprudential factors (e.g., Gibbs 1954; Hanus 1967). This

work led to an empirical focus on “cue theory”: case-specific factors – including the presence

of lower court conflict, the United States as a party, and/or the presence of a civil rights

and liberties issue – that were viewed as strong indicators of a likely grant (Tanenhaus et

al. 1963; Ulmer et al. 1972; Teger and Kosinski 1980; Ulmer 1983, 1984; Armstrong and

Johnson 1982).

A parallel strain of work emphasized the policy content of the cases before the Court.

Schubert’s (1959, 1962) early work on the subject focused on a particular block of justices

who were – in principle – able to bring cases with whose outcomes they disagreed before the

Court and see them overturned (but see Provine 1980). Beginning in the late 1970s, a series

of studies began to further investigate the potential link between policy preferences and the

certiorari decision. Baum’s (1977) study of the California Supreme Court found evidence of

policy-oriented voting on certiorari; that is, justices were found to have voted in a manner

consistent with a consideration of their preferred outcome on the merits.1 Subsequent work

by Songer (1979) and Provine (1980) led to further support for a policy-focused model

of certiorari. In addition, building directly on Schubert’s work, Brenner (1979) developed

an “outcome prediction” model of certiorari voting that emphasized not only the justices’

preferences on the merits, but also their expectations about the likely outcome should the

case be granted. Such “sophisticated” certiorari voting has been borne out by a number of

1See also Ulmer (1972).

1

subsequent studies (Brenner and Krol 1989; Boucher and Segal 1995; Caldeira et al. 1999,

2012).

Contemporary perspectives on the Court’s certiorari process generally synthesize these

various approaches, combining legal/jurisprudential influences with those related to policy

factors (see, e.g., Perry 1991; Epstein et al. 2002; Black and Owens 2009; Owens 2010). Here,

we build upon such synthetic work, focusing on the relatively specific question of interest

group influence on certiorari through submission of briefs amicus curiae. In doing so, we also

back- and update Caldeira and Wright’s (1988) study of amicus effects on certiorari in the

1982 Term.

Amici Curiae and Certiorari

Our starting point is Caldeira and Wright’s (1988) study of amicus curiae influence on

certiorari. Their work integrated previous studies; their theory “predict(ed) that justices will

review the cases they wish to reverse on ideological grounds and the cases they think will

have the greatest practical significance” (1988, 1122). More important from out perspective,

they develop a theory regarding the impact of amicus curiae briefs. Working from the

assumption that “the potential significance of a case is proportional to the demand for

adjudication among affected parties and that the amount of amicus curiae participation

reflects the demand for adjudication” (1988, 1122), they theorize that amicus curiae briefs

serve primarily as costly signals about the policy significance of a case. In this view, amicus

briefs filed at the certiorari stage serve a primarily informational function, alerting the justices

to the presence of cases with the potential for significant policy impact. Importantly, one

implication of this theory is that briefs in opposition to certiorari – which, until recently,

occurred in roughly one out of every 50 paid petitions for certiorari filed – will in effect

be counter productive. That is, because such briefs represent nontrivial investments by

the groups filing them, they indirectly signal the importance of the case, thus raising the

likelihood of certiorari in spite of the arguments presented therein.

Caldeira and Wright’s initial analysis of the 1982 Term found substantial support for a

number of influences on certiorari. Of greatest significance was the fact that amicus briefs by

organized interests were positively related to granting certiorari, even when such briefs urged

that cert be denied. That effect was, however, smaller than that for briefs filed in support

2

of certiorari, which demonstrated slightly declining marginal returns to the number of briefs

filed (1988, 1118). Subsequent analyses have tended to support these findings: Caldeira et

al.’s (1999) analysis of certiorari votes yields similar findings, as does more recent work by

Black and Owens (2009) and Black and Boyd (2012).

But while the association between amicus briefs and grants of certiorari is well estab-

lished, the question of the effect of the former on the latter remains an open one, for at least

two reasons. First, the estimated size of such an effect varies widely from study to study:

Caldeira et al. (1999), for example, estimate the odds ratio for a single pro-certiorari amicus

brief to be 1.66; the corresponding odds ratios for Black and Owens (2009) is roughly 1.35,

and for Black and Boyd (2012) is 1.44.2 Moreover, there is some reason to believe that this

effect has changed over time, particularly with the increasing frequency of amicus filings at

certiorari (see Figure 1, below).

Even more important, however, is the possibility of endogeneity. Theories of interest

group maintenance (e.g., Leighley 1996; Solberg and Waltenburg 2006) suggest that groups

will often undertake costly political activity for reasons beyond (and, in some instances, other

than) the influence of public policy. Retaining and expanding membership, raising operating

funds, enhancing group visibility, and projecting the appearance of political efficacy are all

among the interrelated web of goals faced by organized interests when making decisions

about filing amicus curiae briefs (Hansford 2004). An important consequence of this is that

groups have incentives to file briefs in cases which are – all else equal – more likely to be

granted by the Court. Such endogeneity has been noted in prior work; Caldeira and Wright,

for example, state flatly that “(N)aturally, organizations file briefs amicus curiae for many of

the same reasons as the Supreme Court grants petitions for certiorari. One might, therefore,

suspect simultaneity in our equation” (Caldeira and Wright 1988, n. 18).3 Of course, the

2Recent analyses by Caldeira et al. (2012) find the effects to be even larger.3It bears mentioning that this concern over endogeneity is not limited to academics alone.

For example, in his review of amicus filings at the certiorari stage during the 2006 Term,SCOTUSblog’s Adam Chandler writes that “(O)f course, the influence of a cert-stage amicusbrief should not be overestimated from the success percentages of the top sixteen groups.While the overall success rate of the groups in the chart is far higher than the success rate ofa cert. petition in general (about 27% compared to a general success rate of less than 5% fora paid petition), it also stands to reason that the petitions they throw their weight behindwould alone have a reasonable chance of being granted” (2007).

3

strong likelihood of endogeneity in the relationship between amicus filings and certiorari

outcomes raises serious challenges to any attempt to estimate the effect of the former on the

latter.

In the following analyses, then, our goals are threefold. First, we wish to estimate the

causal effect of amicus curiae briefs on the probability of granting certiorari. Second, and

relatedly, we examine those effects over a broader period of the Court’s history, paying

particular attention to any changes in the effectiveness of amicus briefs over time. Finally,

we hope to reinterrogate and generalize Caldeira and Wright’s (1988) findings on the influence

of briefs in opposition to certiorari.

Data and Analysis

We consider data from four terms of the U.S. Supreme Court (OT 1968, 1982, 1990, and

2007). These terms represent a broad cross section of the past four decades of the Court.

The 1968 Term was arguably the height of Warren Court liberalism, while the 1990 Term

was (at least in terms of its membership) among the most conservative of the Rehnquist

Court. Both the 1982 and 2007 Terms, in contrast, represent more “mixed” Courts, with

the former occurring during a tightly-balanced period of the Burger Court and the latter

during a similarly divided early term of the Roberts Court.4

For each of the four terms, we gathered data on all paid petitions for certiorari; the

numbers of such petitions vary from a low of 1354 in 1968 to a high of 2060 in 1982. In

addition to the outcome of each certiorari petition (granted or denied), we also coded a series

of covariates previous work has shown to be influential in previous work (Caldeira and Wright

1988; Caldeira et al. 1999); these include the presence of the United States as the Petitioner

in the case, a Reversal of the trial court decision in the appellate court below, the presence of

Alleged Conflict, either between circuits, state supreme courts, or with prior Supreme Court

4Interestingly, the relatively homogenous membership of the 1990 Court – Justice Bren-nan’s departure left Justice Marshall as the only Democratic appointee – did not translateinto an overwhelmingly conservative body of work. The 1990 Court decided 46.3 percent ofits cases in a liberal direction on the merits; this compares with 44.9 percent in the 1982term and 50 percent in the 2007 term (the OT1968 Court decided 72.3 percent of its casesliberally) (Spaeth 2010).

4

predecent,5 the presence of a Civil Liberties Issue in the case, the presence of Dissent in

the Lower Court, and whether or not the case raises a Constitutional Claim. Details of the

coding of these variables are presented in the Appendix. Importantly, all of these are factors

that – in addition to having a demonstrated relationship with the probability of a positive

certiorari decision – are among the factors litigants are attuned to looking for in deciding

which cases to support (or oppose) for certiorari.

Following Caldeira and Wright (1988), we code the presence of amicus curiae briefs using

four dichotomous indicators: One Brief in Support of Certiorari, Two or Three Briefs in

Support, Four or More Briefs in Support, and One or More Briefs in Opposition. This

approach allows us to test (in a simple way) for potential nonlinearities in the effects of

briefs on cert.

Figure 1 provides an initial, summary look at the four terms of data analyzed. The

solid line illustrates what lay observers have noted for decades: that, as a fraction of all

petitions filed, the Court has been granting certiorari in an increasingly smaller fraction. In

fact, between 1968 and 2007, the proportion of petitions granted declined by more than 75

percent (from 0.125 to 0.028). Over the same period, however, the fraction of cases with any

degree of amicus activity at the certiorari stage doubled, from 0.05 to 0.10. The substantive

importance of these shifts, however, requires that we dig a bit deeper.

Figure 2 summarizes the associations between amicus filings and grants of certiorari in

our four terms of data. The horizontal axis plots the fraction of cases in which either one,

two or three, four or more, or one+ brief in opposition were filed in each of the four years

in our data, while the vertical axis denotes the proportion of cases of that type that were

granted certiorari. The four horizontal lines indicate the overall grant rates among all paid

petitions during the four indicated terms; these serve as a baseline for comparison.

A close examination of Figure 2 reveals a number of potentially important patterns. One

overwhelmingly clear finding is that certiorari petitions with amicus briefs are granted at an

almost universally higher rate than those without; moreover, in some cases, the differences

are vast. At the same time, for nearly all levels of brief filings, we see a negative association

5For the 1968, 1982, and 1990 Terms we also have a variable denoting Actual Conflict ;however, because we have not (yet) coded that variable for the 2007 Term, we omit it fromour analyses here.

5

between the fraction of cases having briefs and the grant rate. That pattern reflects the

simultaneously upward trends in the numbers of briefs filed over time, and the downward

trend in grant rates for such cases. But the rate of decline in the latter has been significantly

more precipitous than the rate of increase in the latter: the fraction of cases with a two or

three pro-certiorari amicus briefs,6 for example, roughly tripled between 1968 and 2007, but

the grant rate for such cases dropped by nearly 80 percent.

A notable exception to these general patterns is the association between cases with briefs

in opposition to certiorari and grant rates. While grant rates have declined over time in

such cases, the decline has not been monotonic; in fact, the highest grant rate for such

cases is observed during the 1982 Term. Relatedly, beginning in 1982, the rate of filing such

briefs begins to decline, and between 1990 and 2007 drops off significantly. This is in stark

contrast to all other levels of amicus filings, and is related to the fact that only in OT2007

cases with opposition briefs do we observe amici cases with lower grant rates than those

without. While this suggests – at least initially – that briefs in opposition may not have

the unintended consequences attributed to them by Caldeira and Wright, such a conclusion

turns critically on our ability to validly assess the causal effect of such briefs.

To address the potential endogeneity between amici and certiorari, we adopt Sekhon’s

(2011) genetic matching approach. This method – a variant of multivariate Mahalanobis-

distance matching – ensures optimal balance of measured confounders prior to estimation

of causal effects. A crucial aspect of this approach is that our matching algorithm use

data on all potential confounders. Happily, we have strong reasons to believe that the

factors we measure (and match on) are also those which institutional litigants and other

amici consider when making decisions about whether and when to file amicus briefs in

support of or opposition to certiorari. First, the formal and informal criteria used by the

justices in their certiorari decision making are well understood among institutional litigants

and frequent amicus filers alike;7 moreover, nearly all institutional amici retain experienced

outside counsel with extensive appellate practices when filing such briefs. Finally, amici

occasionally indicate their understanding of the criteria for certiorari in public statements

6Note that there were no cases with more than three pro-certiorari amicus curiae briefsin the 1969 Term.

7In fact, each new edition of the “bible” of Supreme Court practice (Gressman et al.2007) typically incorporates findings from empirical legal research on certiorari.

6

about the briefs. For example, following its (unsuccessful) amicus brief supporting certiorari

in Coble v. Texas (Ct. Crim. App. TX. AP-76019), the American Psychological Association

noted publicly that “(T)he denial was likely due to the factors that made a grant a challenge

from the start: the lack of conflict among the federal appellate or state courts on the issue

and the difficulty in reopening (or at least reexamining) Barefoot v. Estelle” (APA 2011).

Accordingly, Figure 3 presents post-matching estimates of the sample average treatment

effect for the treated (ATT) for each of the four amicus curiae variables.8 The points denote

point estimates for the treatment effects, while the vertical lines are 95 percent two-tailed

confidence intervals.

The results in Figure 3 are notable in several respects. We see, for example, a steadily

declining influence of amicus briefs in support of certiorari between the 1968 and 1990 Terms.

That decline levels off between 1990 and 2007, but its net effect is large: the influence of

a single brief, for example, drops from nearly 0.50 to roughly 0.10. While the latter effect

is still statistically distinguishable from zero, it suggests that – in practical terms – the

cert-influencing value of a single amicus brief all but disappeared between the 1960s and the

1990s. A similar pattern holds in cases with two or three briefs, though there the decline

continues until 2007. In contrast, we see no such large drop in cases with large numbers

(four or more) of briefs supporting certiorari; those effects stay relatively constant across the

four terms studied.

The findings for amicus briefs in opposition to certiorari are also telling. In contrast to

earlier work, in no instance do we find an effect of such briefs that is statistically differentiable

from zero. Moreover, the effect sizes are small, and in two of the four terms (1990 and 2007)

negative in sign. The largest-magnitude effect is in 2007, where we expect the probability of

certiorari to decline by 0.18 if such briefs are present. Interestingly, this is nearly identical

to the estimated effect for a single brief in favor of cert during 2007, suggesting that such

briefs currently have the effect of “canceling each other out.”

8We match (with replacement) on the variables listed in the Appendix. Balance diagnos-tics confirm that the matching routine eliminated differences in confounders between caseswith and without the amicus variables in question. These diagnostics are available from theauthors upon request.

7

(Very Brief) Conclusion

Our conclusions are necessarily preliminary; nonetheless, we believe that our findings here

hold substantial implications both for our understanding of the certiorari process in general

and how that process has evolved over the past four decades. One particularly stark finding

bears repeating: At the same time that the number of amicus filings on certiorari have grown

– and perhaps owing to it – the influence of those briefs has steadily declined. From the

Court’s perspective, this is not surprising: a surfeit of amici at the certiorari stage are likely

to dilute the effectiveness of such briefs. But it also suggests that the actual work of the

Court is – perhaps – less influenced by external actors than it has been in the past. If that

is true, it holds implications for the extent to which case selection might bias scholarship on

the Supreme Court (e.g., Kastellec and Lax 2008).

In addition to these implications for the Court, our results also reverberate in the liter-

ature on interest group maintenance and strategy. To the extent that briefs by organized

interests are less effective than in the past, one is tempted to believe that the incentive to

file them has declined as well. Yet they appear in ever-increasing numbers, both at certiorari

and – with a similar level of growth over the past four decades – on the merits. This fact

by itself might indicate that more than simple policy advocacy is at work. In particular, if

increasing numbers of briefs are accompanied by a larger and increasingly diverse popula-

tion of organized interests filing them, one might begin to conclude that groups are viewing

amicus activity in largely group maintenance terms. Like so many others, however, that

question awaits future inquiry.

8

References

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offices/ogc/amicus/coble.aspx. Visited February 12, 2012.

Baum, Lawrence A. 1977. “”Policy Goals in Judicial Gatekeeping: A Proximity Model ofDiscretionary Jurisdiction.” American Journal of Political Science 21:13-35.

Black, Ryan C., and Ryan J. Owens. 2009. “Agenda Setting in the Supreme Court: TheCollision of Policy and Jurisprudence.” Journal of Politics 71:1062-1075.

Black, Ryan C., and Christina L. Boyd. 2012. “U.S. Supreme Court Agenda Setting and theRole of Litigant Status.” Journal of Law, Economics, and Organization 28: forthcoming.

Boucher, Robert L., Jr., and Jeffrey A. Segal. 1995. “Supreme Court Justices as StrategicDecision-Makers: Aggressive Grants and Defensive Denials on the Vinson Court.” Journalof Politics 57:812-823.

Brenner, Saul. 1979. “The New Certiorari Game.” Journal of Politics 41:649-655.

Brenner, Saul, and John F. Krol. 1989. “Strategies in Certiorari Voting on the United StatesSupreme Court.” Journal of Politics 51:828-840.

Caldeira, Gregory A., and John R. Wright. 1988. “Organized Interests and Agenda-Settingin the U.S. Supreme Court.” American Political Science Review 82:1109-1128.

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Caldeira, Gregory A., John R. Wright, and Christopher J. W. Zorn. 1999. “Strategic Votingand Gatekeeping in the Supreme Court.” Journal of Law, Economics and Organization15:549-72.

Caldeira, Gregory A., John R. Wright, and Christopher Zorn. 2012. “A Unified Model ofSupreme Court Voting.” Working paper: Ohio State University.

Chandler, Adam. 2007. “Cert.-stage Amicus Briefs: Who Files Them and To What Effect?”SCOTUSblog. http://www.scotusblog.com/2007/09/cert-stage-amicus-briefs-who-files-them-and-to-what-effect-2/. September 27, 2007.

Epstein, Lee, Je?rey A. Segal and Jennifer Nicoll Victor. 2002. “Dynamic Agenda Settingon the U.S. Supreme Court: An Empirical Assessment.” Harvard Journal on Legislation39:395-433.

Gibbs, Robert W. 1955. “Certiorari: Its Diagnosis and Cure.” Hastings Law Journal 6:139-170.

Gressman, Eugene, Kenneth S. Geller, Stephen M. Shapiro, Timothy S. Bishop, and EdwardA. Hartnett. 2007. Supreme Court Practice, 9th Ed. New York: BNA Books.

Hansford, Thomas G. 2004. “Information Provision, Organizational Constraints, and theDecision to Submit an Amicus Curiae Brief in a U.S. Supreme Court Case.” PoliticalResearch Quarterly 57:219-230.

Hanus, Jerome J. 1967. “Denial of Certiorari and Supreme Court Policy Making.” AmericanUniversity Law Review 17:41-56.

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Kastellec, Jonathan P., and Jeffrey R. Lax. 2008. “Case Selection and the Study of JudicialPolitics.” Journal of Empirical Legal Studies 5:407-446.

Leighley, Janet. 1996. “Group Membership and the Mobilization of Political Participation.”Journal of Politics 58:447-463.

McGuire, Kevin T., and Gregory A. Caldeira. 1993. “Lawyers, Organized Interests, and theLaw of Obscenity: Agenda Setting in the Supreme Court.” American Political ScienceReview 87:717-726.

Owens, Ryan. 2010. “The Separation of Powers and Supreme Court Agenda Setting.”American Journal of Political Science 54:412-427.

Perry, H. W., Jr. 1991. Deciding to Decide: Agenda-Setting in the United States SupremeCourt. Cambridge: Harvard University Press.

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Appendix: Variables and Coding

Liberal Lower Court Decision 1 if the lower court decision was in aliberal policy direction (per Spaeth’s (2009)coding), 0 otherwise.

United States as a Petitioner 1 if the Solicitor General of the United Statesis the petitioning party, 0 otherwise.

Lower Court Reversal 1 if the appellate court immediately below reversedthe lower court’s decision, 0 otherwise.

Alleged Conflict 1 if the petitioning attorney claimed a conflict in oneor more of the following situations, including conflictbetween two or more state supreme courts, conflictbetween two or more federal circuit courts, conflictbetween a state court and a federal court, andconflict with a precedent of the Supreme Court;0 otherwise.

Civil Liberties Issue 1 if the case raised a question of civil rights orliberties, 0 otherwise.

Dissent in Lower Court 1 if a judge in the court immediately below filed adissent, 0 otherwise.

Constitutional Claim 1 if the petitioner or appellant made a legal claimbased on a provision of the United Statesconstitution, 0 otherwise.

One Amicus Brief for Certiorari 1 if one brief amicus curiae was filed in support ofcertiorari, 0 if more than one brief or no briefswere filed.

Two or Three Briefs for Certiorari 1 if two or three amicus curiae briefs were filedin support of certiorari, 0 otherwise.

Four or More Briefs for Certiorari 1 if four or more amicus curiae briefs were filedin support of certiorari, 0 otherwise.

One or More Briefs Against Certiorari 1 if one of more amicus curiae briefs werefiled in opposition to certiorari, 0 otherwise.

11

Figure 1: Certiorari Grant Rates, by Year

1970 1980 1990 2000 2010

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

Year

Pro

porti

on o

f Cas

es

Proportion with ≥ One Amicus Brief

Proportion Granted

Note: Figure plots the proportion of all paid petitions for certiorari granted bythe Court (solid line) and the proportion of cases with at least one amicus curiaebrief filed at the certiorari stage (dotted line) during the 1968, 1982, 1990, and2007 Terms.

12

Figure 2: Proportions of Cases and Grant Rates at Different Levels of Amicus Activity1968

1968

19681982

1982

19821990

1990

19902007

2007

20071968

1968

19681982

1982

19821990

1990

19902007

2007

20071968

1968

19681982

1982

19821990

1990

19902007

2007

20071982

1982

19821990

1990

19902007

2007

20071968

1968

19681982

1982

19821990

1990

19902007

2007

2007Any Brief(s)

Any Brief(s)

Any Brief(s)One Brief in Support

One Brief in Support

One Brief in SupportTwo or Three Briefs in Support

Two or Three Briefs in Support

Two or Three Briefs in SupportFour or More Briefs in Support

Four or More Briefs in Support

Four or More Briefs in SupportOne or More Brief(s) in Opposition

One or More Brief(s) in Opposition

One or More Brief(s) in Opposition0

0

0.2

.2

.2.4

.4

.4.6

.6

.6.8

.8

.8Grant Rate

Gra

nt R

ate

Grant Rate0

0

0.02

.02

.02.04

.04

.04.06

.06

.06.08

.08

.08.1

.1

.1Amicus Filing Rate

Amicus Filing Rate

Amicus Filing Rate1968

1968

19681982

1982

19821990

1990

19902007

2007

2007

Note: Figure plots the proportion of cases having one, two or three, or fouror more briefs in support of certiorari, or one or more brief in opposition tocertiorari, against the proportion of all paid petitions of each type granted bythe Court during the 1968, 1982, 1990, and 2007 Terms. Dashed horizontal linesare the overall grant rates for each of the four terms. See text for details.

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Figure 3: Estimated Effects of Amici on Pr(Certiorari)

1970 1980 1990 2000 2010

0.0

0.5

1.0

Year

Effe

ct o

f One

Brie

f

1970 1980 1990 2000 2010

0.0

0.5

1.0

Year

Effe

ct o

f Tw

o or

Thr

ee B

riefs

1970 1980 1990 2000 2010

0.0

0.5

1.0

Year

Effe

ct o

f Fou

r or M

ore

Brie

fs

1970 1980 1990 2000 2010

0.0

0.5

1.0

Year

Effe

ct o

f One

+ O

ppos

ition

Brie

fs

Note: Figure plots the post-matching estimate of the sample average treatmenteffect for the treated (ATT) of one, two or three, or four or more briefs in supportof certiorari, or one or more brief in opposition to certiorari for the 1968, 1982,1990, and 2007 Terms. Vertical lines denote 95 percent two-tailed confidenceintervals. See text for details.

14