 United States Court of Appeals
         FOR THE DISTRICT OF COLUMBIA CIRCUIT



Argued October 18, 2018               Decided April 19, 2019

                        No. 17-5278

                      DANIEL BARKER,
                        APPELLANT

                             v.

            PATRICK CONROY, CHAPLAIN, ET AL.,
                       APPELLEES


        Appeal from the United States District Court
                for the District of Columbia
                    (No. 1:16-cv-00850)


     Andrew Seidel argued the cause for appellant. On the
briefs was Richard L. Bolton. Anita T. Gallucci entered an
appearance.

     Alison Gill was on the brief for amici curiae The Center
for Inquiry and American Atheists in support of appellant.

    Gregory M. Lipper was on the brief for amici curiae
Representatives Mark Pocan, Jared Huffman, and Jamie
Raskin in support of appellant and reversal.

    Richard B. Katskee, Alex J. Luchenitser, and Jeffrey I.
Pasek were on the brief for amici curiae Americans United for
                              2
Separation of Church and State, et al. supporting appellant and
reversal.

   Monica L. Miller was on the brief for amicus curiae The
American Humanist Association in support of appellant.

    Thomas G. Hungar, General Counsel, U.S. House of
Representatives, argued the cause and filed the brief for
appellees. Matthew M. Collette and Lowell V. Sturgill Jr.,
Attorneys, U.S. Department of Justice, entered appearances.

     Mike Hunter, Attorney General, Office of the Attorney
General for the State of Oklahoma, Mithun Mansinghani,
Solicitor General, Steve Marshall, Attorney General, Office of
the Attorney General for the State of Alabama, Leslie Rutledge,
Attorney General, Office of the Attorney General for the State
of Arkansas, Mark Brnovich, Attorney General, Office of the
Attorney General for the State of Arizona, Cynthia H. Coffman,
Attorney General, Office of the Attorney General for the State
of Colorado, Christopher M. Carr, Attorney General, Office of
the Attorney General for the State of Georgia, Doug Peterson,
Attorney General, Office of the Attorney General for the State
of Nebraska, Michael DeWine, Attorney General, Office of the
Attorney General for the State of Ohio, Alan Wilson, Attorney
General, Office of the Attorney General for the State of South
Carolina, Ken Paxton, Attorney General, Office of the
Attorney General for the State of Texas, Sean D. Reyes,
Attorney General, Office of the Attorney General for the State
of Utah, Patrick Morrisey, Attorney General, Office of the
Attorney General for the State of West Virginia, Brad Schimel,
Attorney General, Office of the Attorney General for the State
of Wisconsin, Lawrence G. Wasden, Attorney General, Office
of the Attorney General for the State of Idaho, Curtis T. Hill,
Jr., Attorney General, Office of the Attorney General for the
State of Indiana, Derek Schmidt, Attorney General, Office of
                               3
the Attorney General for the State of Kansas, Jeff Landry,
Attorney General, Office of the Attorney General for the State
of Louisiana, and Tim Fox, Attorney General, Office of the
Attorney General for the State of Montana, were on the brief
for amici curiae The States of Oklahoma, et al. in support of
appellees.

     Eric S. Baxter was on the brief for amici curiae Aleph
Institute, et al. in support of defendants-appellees and
affirmance.

     Jonathan A. Scruggs, Kristen K. Waggoner, David A.
Cortman, and Nathaniel P. Bruno were on the brief for amici
curiae 48 Members of Congress in support of appellees and
affirmance.

    Steffen N. Johnson, John W.H. Harding, Paul N. Harold,
and Stephanie A. Maloney were on the brief for amici curiae
Jewish Coalition for Religious Liberty, et al. supporting
appellees and affirmance.

    Before: TATEL, Circuit Judge, and EDWARDS and
GINSBURG, Senior Circuit Judges.

    Opinion for the Court filed by Circuit Judge TATEL.

     TATEL, Circuit Judge: Since 1789, the House of
Representatives has begun each legislative day with a prayer, a
practice the Supreme Court has found compatible with the
Establishment Clause. See generally Marsh v. Chambers, 463
U.S. 783 (1983). Although a House-appointed chaplain has
traditionally delivered the opening prayer, at some time in the
past the House began allowing members to nominate other
individuals to give a prayer as “guest chaplain.” This case arose
when a member of the House asked the Chaplain, Father
                                4
Patrick J. Conroy, to invite Daniel Barker—a former Christian
minister turned atheist—to serve as guest chaplain and deliver
a secular invocation. Conroy denied the request, and Barker
sued, alleging that Conroy unconstitutionally excluded him
from the guest chaplain program because he is an atheist. The
district court dismissed Barker’s Establishment Clause claim
for lack of Article III standing and for failure to state a claim.
Although we find that Barker has standing to challenge his
exclusion from the program, we affirm the district court’s
dismissal because he has failed to state a claim upon which
relief can be granted.

                                I.
     Because this case comes to us on appeal from the district
court’s grant of a motion to dismiss, “we must accept as true
all material allegations of the complaint, drawing all reasonable
inferences from those allegations in” Barker’s favor. LaRoque
v. Holder, 650 F.3d 777, 785 (D.C. Cir. 2011) (internal
quotation marks omitted). Viewed through that lens, the
complaint relates the following.

     House of Representatives Rule II, clause 5 provides that
“[t]he Chaplain shall offer a prayer at the commencement of
each day’s sitting of the House.” H.R. Doc. No. 114-192, Rule
II, cl. 5 (2017). The House also allows guest chaplains to
deliver the opening prayer, although the chamber’s rules make
no provision for that practice. In the last fifteen years, guest
chaplains have delivered approximately forty percent of all
invocations. The House’s Office of the Chaplain approves
guest chaplains and coordinates their visits. Between 2000 and
2015, although the vast majority of individuals allowed to
deliver opening prayers were Christian, the House also
welcomed guest chaplains of the Muslim, Jewish, and Hindu
faiths. The House has never had an openly atheist or agnostic
guest chaplain.
                                5

    In 2014, Daniel Barker sought to be the first self-professed
atheist to serve as guest chaplain. Barker is co-president of the
Freedom From Religion Foundation, “a non-profit that
promotes non-belief and works to keep state and church
separate.” Complaint for Declaratory and Injunctive Relief
(“Compl.”) ¶ 13. Ordained to the Christian ministry in the mid-
1970s, Barker spent nearly twenty years as a pastor and
missionary before he “‘lost faith in faith’ and became an
atheist.” Id. ¶ 16. Although “nonreligious,” id. ¶ 4, Barker
“views the opportunity to give an invocation [before the
House] . . . as a great honor and an opportunity to participate in
solemnizing the venerable work of the U.S. government,” id.
¶ 67.

     When the Freedom From Religion Foundation first
inquired about the possibility of Barker delivering an
invocation, the House Chaplain’s Office explained that,
although the program has no written rules, guest chaplains are
permitted to give invocations only if they meet three
requirements: “(1) they are sponsored by a member of the
House, (2) they are ordained, and (3) they do not directly
address House members and instead address a ‘higher power.’”
Id. ¶ 35. Barker easily satisfied the first two requirements: his
congressman, Representative Mark Pocan, agreed to sponsor
him, and Barker provided the Chaplain’s Office with his
ordination certificate. Demonstrating that he could also satisfy
the third requirement, Barker sent the Chaplain’s Office a copy
of his draft secular invocation, which invoked “the ‘higher
power’ of human wisdom,” but no God or other religious
higher power. Compl., Ex. B.

    Four months passed without word from the Chaplain’s
Office. Asked about the delay, a Chaplain’s Office employee
responded that the Office “did not think [Barker’s] requests
                               6
were ‘genuine.’” Id. ¶ 46. Then, in December 2015, the
Chaplain’s Office formally rejected Barker’s application
because he “was ordained in a denomination in which he no
longer practices.” Id. ¶ 111 (internal quotation marks omitted).
Conroy repeated this explanation in a January 2016 letter to
Representative Pocan, which he began by “[l]eaving aside” two
questions: “(i) whether the ‘secular invocation’ that . . . Mr.
Barker proposed to deliver would constitute a ‘prayer’ within
the meaning of the House Rules, and (ii) if not, whether
[Conroy] could permit Mr. Barker to deliver such an invocation
consistent with [his] responsibilities under the House Rules.”
Compl., Ex. C at 1. Conroy went on to explain that he was
“unable to accede to [Pocan’s] recommendation for a more
basic, threshold reason”: as a “‘Minister Turned Atheist’” and
“author of several books that concern his parting with his
religious beliefs,” Barker did not meet the “long-standing
requirement” that all guest chaplains “be ordained by a
recognized body in the faith in which [they] practice[].” Id.
at 1–2.

     Barker sued Conroy and several others, including the
House of Representatives and then-Speaker Paul Ryan,
alleging violations of the First Amendment’s Establishment
Clause, among other claims. In his complaint, he presented
several different, albeit related, theories as to how Conroy’s
actions violated the Establishment Clause. Barker first alleged
that Conroy’s unwritten requirements that guest chaplains be
ordained and address a higher power create a preference for
religion over nonreligion and “discriminate against those
whose religious beliefs do not include a belief in a supernatural
higher power [and] those who practice a religion that does not
have ordinations.” Compl. ¶ 160. Next, Barker contended that
Conroy unevenly enforces those requirements “in a manner
that excludes atheists and other minority religions.” Id. ¶ 161.
Specifically, Barker asserted that the Chaplain’s Office “has
                               7
not enforced the same requirements against other, religious
applicants” for the guest chaplain program. Id. ¶ 119. Finally,
Barker alleged that Conroy’s reasons for excluding him from
the program were pretextual and that Conroy actually denied
him the opportunity to serve as guest chaplain simply because
he is an atheist. Barker sought broad declaratory and injunctive
relief as well as a writ of mandamus requiring Conroy to allow
him to deliver an invocation “as soon as possible.” Id. at 28.

     Conroy moved to dismiss on the grounds that Barker
lacked Article III standing and that the case was nonjusticiable
under the political question doctrine and the Speech or Debate
Clause of the U.S. Constitution. On the merits, Conroy argued
that Barker failed to state a claim for which relief could be
granted under the Establishment Clause.

     The district court granted the motion to dismiss. Although
it found Barker’s suit barred by neither the political question
doctrine nor the Speech or Debate Clause, it concluded that
Barker lacked Article III standing to pursue his Establishment
Clause claim. Specifically, the district court determined that
Barker failed to establish that Conroy caused his claimed
injuries because Barker never alleged that the House Chaplain
had authority to permit him to deliver a secular invocation
during the time reserved for prayer. In the alternative, the
district court concluded that Barker failed to state an
Establishment Clause claim because his suit was effectively “a
challenge to the ability of Congress to open with a prayer.”
Barker v. Conroy, 282 F. Supp. 3d 346, 364 (D.D.C. 2017).
Such a challenge, the court explained, was foreclosed by the
Supreme Court’s endorsement of legislative prayer in both
Marsh v. Chambers and Town of Greece v. Galloway, 572 U.S.
565, 570 (2014) (holding that the practice of opening town
board meetings with a sectarian prayer that was often Christian
did not violate the Establishment Clause).
                               8

     On appeal, Barker pursues only his Establishment Clause
claim against Conroy in his official capacity. Our review is de
novo. See Washington Alliance of Technology Workers v. U.S.
Department of Homeland Security, 892 F.3d 332, 339 (D.C.
Cir. 2018) (“We review the district court’s dismissal of a
complaint for lack of standing or for failure to state a claim de
novo.”).

     Before we proceed to that review, however, a final note is
in order. The record regarding the undisputed facts in this case
is somewhat unusual given that, since Barker filed his
complaint, Conroy has clarified that the House interprets its
rules to require a religious prayer. As explained above, when
Conroy rejected Barker’s application to serve as guest
chaplain, he expressly “le[ft] aside the question[] of . . .
whether the ‘secular invocation’ that . . . Mr. Barker proposed
to deliver would constitute a ‘prayer’ within the meaning of the
House Rules.” Compl., Ex. C at 1. Instead, Conroy told
Representative Pocan, Barker was disqualified for the “more
basic, threshold reason” that he is not “ordained by a
recognized body in the faith in which he[] practices.” Id. at 1–
2.

     But during the course of this litigation, Conroy has taken
a different position: that Barker could not serve as guest
chaplain because he sought to give a secular prayer. More
important, the House of Representatives itself, through House
counsel, has now ratified that position. Both in briefing and at
oral argument, House counsel represented to this court that the
House interprets its rules to require “a religious invocation.”
Appellees’ Br. 39. “What I’m saying,” counsel explained at
oral argument, “and what the House is saying, and has
authorized me to say . . . is, as explained in our briefs below
and in this court, that persons who desire to deliver a secular
                                9
invocation in lieu of a prayer, as the House interprets its prayer
rule and has consistently applied it for 225 years, are not
entitled to do so.” Oral Arg. Rec. 38:32–39:01. Barker, who
seeks to deliver a nonreligious prayer, counters that legislative
prayer need not be religious, but he nowhere disputes House
counsel’s representation that the House interprets its rules to
require a religious prayer. See Reply Br. 5 (“Father Conroy . . .
argue[s] that legislative invocations necessarily must be
religious in substance and purpose.”). As we shall explain
below, although House counsel’s representation is irrelevant to
Barker’s Article III standing, it is critical to the merits of this
case.

                                II.
     As “the party invoking federal jurisdiction,” Barker “bears
the burden of establishing” Article III standing. Spokeo, Inc. v.
Robins, 136 S. Ct. 1540, 1547 (2016). To satisfy that burden,
Barker must allege facts demonstrating that he “(1) suffered an
injury in fact, (2) that is fairly traceable to the challenged
conduct of the defendant, and (3) that is likely to be redressed
by a favorable judicial decision.” Id. At the pleading stage—
the situation here—the plaintiff is “required only to ‘state a
plausible claim’ that each of the standing elements” existed at
the time the complaint was filed. Attias v. Carefirst, Inc., 865
F.3d 620, 625 (D.C. Cir. 2017) (quoting Food & Water Watch,
Inc. v. Vilsack, 808 F.3d 905, 913 (D.C. Cir. 2015)); see also
Wheaton College v. Sebelius, 703 F.3d 551, 552 (D.C. Cir.
2012) (“[S]tanding is assessed at the time of filing . . . .”). For
purposes of the standing inquiry, we assume Barker would
succeed on the merits of his claim. See Schnitzler v. United
States, 761 F.3d 33, 40 (D.C. Cir. 2014) (“[I]n reviewing the
standing question, the court must . . . assume that on the merits
the plaintiffs would be successful in their claims.” (internal
quotation marks omitted)).
                               10
     In concluding that Barker lacked Article III standing based
on a failure to plausibly allege causation, the district court
relied on this court’s decision in Kurtz v. Baker, which
addressed a challenge to the House and Senate Chaplains’
refusal to allow a secular humanist to deliver nonreligious
remarks as a “guest speaker” during the period reserved for
morning prayer. 829 F.2d 1133, 1134 (D.C. Cir. 1987). We
concluded that the plaintiff’s claimed exclusion injury—his
inability to address the House or Senate—was not fairly
traceable to the chaplains’ refusal to allow him to deliver
secular remarks during the time set aside for prayer “because
(1) there [was] no allegation that the chaplains had discretion
to grant [his] requests, and (2) such an allegation would in any
event [have been] untenable.” Id. at 1142.

     This case is very different. In Kurtz, the plaintiff had no
intention of delivering a prayer, seeking instead to “address
[the House and Senate] ‘[o]n behalf of the Council for
Democratic and Secular Humanism.’” Id. at 1135 (second
alteration in original) (quoting Letter from Dr. Kurtz to Rev.
Halverson (Feb. 13, 1984); Letter from Dr. Kurtz to Rev. Ford
(Feb. 13, 1984)). Kurtz “‘request[ed] the opportunity to appear
as a guest speaker and to open a daily session . . . with a short
statement in which [he] would remind the [members of the
Senate and the House] of their moral responsibilities.’” Id.
(alterations in original) (quoting Letter from Dr. Kurtz to Rev.
Halverson; Letter from Dr. Kurtz to Rev. Ford). He “advised
both chaplains that he would not utter a prayer if invited.” Id.
By contrast, Barker has never said that he is unwilling to utter
a prayer, saying instead that the invocation he wishes to give is
“secular.” See, e.g., Compl., Ex. A (“[Barker] intends for his
invocation to be secular . . . .”); see also Invocation, Merriam-
Webster’s Collegiate Dictionary (10th ed. 1997) (defining
“invocation” as “a prayer of entreaty (as at the beginning of a
service of worship)”); Oral Arg. Rec. 0:58–1:12 (Barker’s
                                11
counsel: “Dan Barker was invited by his representative to do
something hundreds of other individuals have done: deliver a
prayer at the U.S. House of Representatives. In his prayer,
Barker wanted to invoke unifying and solemn themes . . . .”
(emphases added)).

     Although, historically, prayers delivered in the House have
been religious, the rules themselves refer only to “prayer”; they
make no distinction between religious and secular prayer. See
H.R. Doc. No. 114-192, Rule II, cl. 5 (“The Chaplain shall offer
a prayer at the commencement of each day’s sitting of the
House.”); id. Rule XIV, cl. 1 (listing “[p]rayer by the Chaplain”
as the first order of business). And, as a matter of ordinary
usage, it is at least plausible that the word “prayer”
encompasses a secular invocation. See Prayer, Webster’s Third
New International Dictionary (2002) (defining “prayers” as
“earnest good wishes”); Prayer, Thomas Dyche & William
Pardon, A New General English Dictionary: Peculiarly
Calculated for the Use and Improvement of Such as Are
Unacquainted with the Learned Languages (14th ed. 1771)
(defining “prayer” as “an earnest request, desire, or petition put
up to God, or some other person or persons” (emphasis
added)). To be sure, through House counsel, Conroy now
insists that a “prayer,” as contemplated by the House rules,
must be religious. But Conroy offered that interpretation only
after Barker filed his complaint and, as noted above, standing
is assessed at the time of filing. See supra at 9. Indeed, when
Conroy rejected Barker’s application, he expressly “le[ft] aside
the question[] of . . . whether the ‘secular invocation’ that . . .
Mr. Barker proposed to deliver would constitute a ‘prayer’
within the meaning of the House Rules.” Compl., Ex. C at 1.
Instead, he explained, he was unable to allow Barker to serve
as guest chaplain “for a more basic, threshold reason.” Id.
Moreover, in contrast to Kurtz, where “there [was] no
allegation that the chaplains had discretion to grant [the
                               12
plaintiff’s] requests,” 829 F.2d at 1142, Barker’s complaint
contains factual allegations that Conroy, apparently without
objection from members of the House, has allowed certain
guest chaplains to deliver prayers that did not invoke a divine
power. See Compl. ¶¶ 146–151. Accepting Barker’s well-
pleaded factual allegations as true and drawing “all reasonable
inferences” in Barker’s favor, LaRoque, 650 F.3d at 785, we
therefore conclude it was at least plausible at the time Barker
filed his complaint that Conroy had discretion and authority
under the House rules to grant his request to deliver a secular
invocation.

      Barker easily satisfies the other requirements for Article
III standing. His inability to deliver a secular prayer before the
House as a result of his exclusion from the guest chaplain
program qualifies as a cognizable injury in fact, see Kurtz, 829
F.2d at 1142, and that injury would be redressed by a decision
declaring the current practice unconstitutional and ordering
Conroy to “schedule Barker to give an invocation as soon as
possible,” Compl. at 28. That said, to the extent Barker seeks
relief untethered to his particular injury—he challenges other,
more general aspects of the guest chaplain program, such as
“the requirement that guest chaplains be ordained and
practicing in the religion in which they were ordained,” id.
¶ 157, and the alleged exclusion of all “atheists and other
nonreligious individuals from the position of guest chaplain,”
id. at 27—he has standing to request such relief only on behalf
of himself and those who, like him, desire to deliver a secular
prayer. See, e.g., Lewis v. Continental Bank Corp., 494 U.S.
472, 477 (1990) (“Article III denies federal courts the power
‘to decide questions that cannot affect the rights of litigants in
the case before them.’” (quoting North Carolina v. Rice, 404
U.S. 244, 246 (1971) (per curiam))).
                               13
     Nor does Barker’s Establishment Clause claim present a
nonjusticiable political question. A claim raises such a question
if it involves “a textually demonstrable constitutional
commitment of the issue to a coordinate political department.”
Baker v. Carr, 369 U.S. 186, 217 (1962). Conroy argues that
Barker’s claim does just that, as it “involves the textually
demonstrable constitutional commitment of exclusive
authority to the House to ‘determine the Rules of its
Proceedings.’” Appellees’ Br. 29 (quoting U.S. Const. art. I,
§ 5, cl. 2). But even accepting the belated contention that the
House defines “prayer” as religious prayer—a qualification
that, once again, appears nowhere in the text of the House
rules—Barker’s Establishment Clause claim remains
justiciable. As the Supreme Court has long held, although “the
[C]onstitution empowers each house to determine its rules of
proceedings,” Congress “may not by its rules ignore
constitutional restraints or violate fundamental rights.” United
States v. Ballin, 144 U.S. 1, 5 (1892); see also Vander Jagt v.
O’Neill, 699 F.2d 1166, 1173 (D.C. Cir. 1983) (“Article I does
not alter our judicial responsibility to say what rules Congress
may not adopt because of constitutional infirmity.”). In this
case, rather than challenging the House rules themselves,
Barker argues that any interpretation or application of the rules
that prevents atheists from serving as guest chaplains violates
the Establishment Clause. But just as the Rulemaking Clause
gives Congress no license to adopt unconstitutional rules, it
provides no cover for the House to unconstitutionally interpret
or apply its rules.

    The Speech or Debate Clause likewise poses no bar to
Barker’s claim, even assuming legislative immunity could ever
extend to the House Chaplain. Declaring that “Senators and
Representatives . . . for any Speech or Debate in either
House . . . shall not be questioned in any other Place,” U.S.
Const. art. I, § 6, cl. 1, that clause immunizes both legislators
                              14
and their aides from criminal and civil suits arising out of
“legislative acts,” Rangel v. Boehner, 785 F.3d 19, 23 (D.C.
Cir. 2015) (internal quotation marks omitted); see also Gravel
v. United States, 408 U.S. 606, 618 (1972) (“[T]he Speech or
Debate Clause applies not only to a Member but also to his
aides insofar as the conduct of the latter would be a protected
legislative act if performed by the Member himself.”). In order
to ensure “that the legislative function the Constitution
allocates to Congress may be performed independently,”
Eastland v. United States Servicemen’s Fund, 421 U.S. 491,
502 (1975), we “have extended the privilege to matters beyond
pure speech or debate in either House, but only when necessary
to prevent indirect impairment of such deliberations,” Gravel,
408 U.S. at 625 (internal quotation marks omitted).
Accordingly, the Clause’s protections extend to acts that are
“an integral part of the deliberative and communicative
processes by which Members participate in committee and
House proceedings with respect to the consideration and
passage or rejection of proposed legislation or with respect to
other matters which the Constitution places within the
jurisdiction of either House.” Id.

     Unlike acts protected by the Speech or Debate Clause—
such as voting and other committee activities like “authorizing
an investigation, holding hearings, preparing a report, and
authorizing the publication and distribution of that report,”
United States v. Rose, 28 F.3d 181, 187–88 (D.C. Cir. 1994)
(internal quotation marks omitted)—legislative prayer is not
“an integral part of the deliberative and communicative
process[],” Gravel, 408 U.S. at 625; see also Kurtz, 829 F.2d
at 1146 n.2 (Ginsburg, R.B., J., dissenting) (“While
inspirational, prayer in Congress does not appear to be integral
to lawmaking.” (internal quotation marks omitted)). Although
the Supreme Court has instructed us to “read the Speech or
Debate Clause broadly to effectuate its purposes,” Eastland,
                                15
421 U.S. at 501, the Clause’s “shield does not extend beyond
what is necessary to preserve the integrity of the legislative
process,” United States v. Brewster, 408 U.S. 501, 517 (1972).
Because Barker’s challenge to Conroy’s administration of the
guest chaplain program presents no apparent threat to
lawmakers’ independence, the Speech or Debate Clause offers
Conroy no immunity from Barker’s Establishment Clause
challenge. See Gravel, 408 U.S. at 618 (describing the
“fundamental purpose” of the Clause as “freeing the legislator
from executive and judicial oversight that realistically
threatens to control his conduct as a legislator”).

     Nothing in Consumers Union of United States, Inc. v.
Periodical Correspondents’ Ass’n, 515 F.2d 1341 (D.C. Cir.
1975), requires a different result. There we rejected as
nonjusticiable an organization’s challenge to the denial of its
application for admission to the House and Senate press
galleries because the denial fell “within the spheres of
legislative power committed to the Congress and the legislative
immunity granted by the Constitution.” Id. at 1351. We first
observed that the entity responsible for denying the
organization’s application, the Executive Committee of the
Periodical Correspondents’ Association (the “Association”),
had acted pursuant to internal congressional rules governing
admission to the galleries. Id. at 1347, 1350. Because the
Constitution expressly reserves to the legislative branch the
power to make its own internal rules, we explained, Congress’s
“power over [its] internal proceedings . . . in itself would
appear to establish the nonjusticiability of this cause were it not
for the contention that” the rule at issue—and the Association’s
interpretation of it—“infringed upon [the organization’s]
constitutional rights.” Id. at 1347–48; see also Ballin, 144 U.S.
at 5 (Congress “may not by its rules ignore constitutional
restraints or violate fundamental rights”). We then “turn[ed] to
the effect of the Speech or Debate Clause to settle whether
                                16
despite the claim of constitutional violation . . . [the] case [was]
yet nonjusticiable,” Consumers Union, 515 F.2d at 1348,
ultimately concluding that the Association’s denial of the
organization’s application “fell within the sphere of legislative
activity” protected by the Clause, id. at 1350 (internal quotation
marks omitted). Essential to that determination was the fact that
Congress itself had developed the press gallery rules to protect
legislators’ independence: Congress designed the rules to
ensure that the galleries would “be used by bona fide reporters
who [would] not abuse the privilege of accreditation by
importuning Members on behalf of private interests or causes.”
Id. at 1347. As we explained in a later case, because the
Association’s denial of the organization’s application involved
“regulation of the very atmosphere in which lawmaking
deliberations occur,” the Speech or Debate Clause barred us
from hearing the suit. Walker v. Jones, 733 F.2d 923, 930 (D.C.
Cir. 1984) (emphasis added).

     Unlike the plaintiff organization in Consumers Union,
Barker does not mount a facial challenge to the House’s rules
and, even if he did, the political question doctrine would pose
no bar to such a suit. See supra at 13. Moreover, any rules
pertaining to the opening prayer—an event that occurs at the
very beginning of the legislative session before any
deliberating whatsoever—could not similarly be said to
regulate “the very atmosphere in which lawmaking
deliberations occur.” Walker, 733 F.2d at 930. The Supreme
Court itself has described legislative prayer not as a part of the
legislative process, but rather as a “symbolic expression” that
simply “lends gravity to public business, reminds lawmakers to
transcend petty differences in pursuit of a higher purpose, and
expresses a common aspiration to a just and peaceful society.”
Town of Greece, 572 U.S. at 575. By contrast to the conduct
challenged in Consumers Union, then, Conroy’s administration
of the guest chaplain program is not “an integral part of the
                                17
[House’s] deliberative and communicative processes.” 515
F.2d at 1349 (quoting Gravel, 408 U.S. at 625). Judicial review
of Conroy’s conduct thus poses no threat to “the integrity of the
legislative process.” Brewster, 408 U.S. at 517.

                                III.
     Barker contends that the Establishment Clause’s general
requirement that the government be “neutral in its relations
with groups of religious believers and non-believers,” Everson
v. Board of Education of Ewing Township, 330 U.S. 1, 18
(1947), and the Supreme Court’s decision in Town of Greece v.
Galloway prohibit Conroy from excluding atheists like him
from the guest chaplain program. For his part, Conroy argues
that Barker’s suit amounts to “an attack on the practice of
legislative prayer itself” and that the district court was therefore
correct that Barker failed to state a plausible Establishment
Clause claim under the Supreme Court’s legislative prayer
precedents. Appellees’ Br. 39.

     The starting point for our analysis is Marsh v. Chambers,
which involved an Establishment Clause challenge to the
Nebraska Legislature’s practice of opening legislative sessions
with a Judeo-Christian prayer given by a taxpayer-funded
chaplain. See 463 U.S. at 784–85. Eschewing reliance on the
three-part Lemon test typically used to assess alleged
Establishment Clause violations, the Court instead looked to
the history of legislative prayer. See id. at 786–92. That history,
the Court explained, “sheds light not only on what the
draftsmen intended the Establishment Clause to mean, but also
on how they thought that Clause applied.” Id. at 790. The Court
thought it especially significant that the very same Congress
that passed the Bill of Rights also authorized the appointment
of paid chaplains, whose duties included delivering an opening
prayer. See id. at 788. “It can hardly be thought that in the same
week Members of the First Congress voted to appoint and to
                               18
pay a Chaplain . . . and also voted to approve the draft of the
First Amendment . . . , they intended the Establishment
Clause . . . to forbid what they had just declared acceptable.”
Id. at 790; see also id. at 788 (“Clearly the men who wrote the
First Amendment Religion Clause did not view paid legislative
chaplains and opening prayers as a violation of that
Amendment, for the practice of opening sessions with prayer
has continued without interruption ever since that early session
of Congress.”). Given its “unique history,” the Court
concluded, legislative prayer did not run afoul of the
Establishment Clause. Id. at 791.

     Observing that the Nebraska Legislature’s particular
prayer practice was “similar” to that of the First Congress, id.,
the Court went on to consider whether it nonetheless violated
the Establishment Clause because (1) the same Presbyterian
clergyman had served as the legislature’s chaplain and primary
prayer-giver for sixteen years, (2) the chaplain was “paid at
public expense,” and (3) the prayers he gave were “in the
Judeo-Christian tradition,” id. at 793. Weighing these features
“against the historical background” of legislative prayer, the
Court upheld the constitutionality of Nebraska’s practice. Id.
The Court indicated, however, that it might have reached a
different conclusion if there had been “proof that the chaplain’s
reappointment stemmed from an impermissible motive” rather
than from satisfaction with his performance and personal
qualities, id., or any “indication that the prayer opportunity
ha[d] been exploited to proselytize or advance any one, or to
disparage any other, faith or belief,” id. at 794–95.

    The Supreme Court revisited legislative prayer and
elaborated on the principles underlying Marsh in Town of
Greece v. Galloway. That case involved an Establishment
Clause challenge to a town’s practice of inviting volunteers
from religious congregations to deliver an opening prayer at the
                                19
town’s monthly board meetings. See 572 U.S. at 569–72. In its
recitation of the facts the Court emphasized that “[t]he town at
no point excluded or denied an opportunity to a would-be
prayer giver. Its leaders maintained that a minister or layperson
of any persuasion, including an atheist, could give the
invocation.” Id. at 571. The challengers nonetheless contended
that the town’s prayer program violated the Establishment
Clause because the town allowed sectarian prayers that were,
in practice, primarily Christian. See id. at 572. The Court began
with Marsh, describing it as “stand[ing] for the proposition that
it is not necessary to define the precise boundary of the
Establishment Clause where history shows that the specific
practice is permitted.” Id. at 577. Using the legislative-prayer
tradition described by Marsh as its measuring stick, the Court
proceeded to evaluate whether any aspect of the town’s prayer
practice fell outside the bounds of that tradition. Finding that
neither the sectarian content of the town’s prayers nor their
predominantly Christian character was inconsistent with “the
tradition long followed in Congress and the state legislatures,”
id., the Court concluded that the prayer practice was
constitutional, “[s]o long as the town maintains a policy of
nondiscrimination,” id. at 585.

     Together, Marsh and Town of Greece establish a two-step
process for assessing the constitutionality of a particular
legislative-prayer practice: identify the essential characteristics
of the practice and then determine whether that practice falls
within the tradition the Supreme Court has recognized as
consistent with the Establishment Clause.

     As to the first inquiry, although at the time Barker filed his
complaint it was plausible that the rules allowed for delivery of
a secular invocation, see supra at 10–12, the House has since
definitively ruled out that possibility. Timing matters. When
determining whether a complaint states a claim, we are not
                              20
confined by the circumstances existing “at the time of filing,”
as we are when assessing Article III standing. Wheaton
College, 703 F.3d at 552. To be sure, given that “Rule 12(b)(6)
is not a device for testing the truth of what is asserted,” ACLU
Foundation of Southern California v. Barr, 952 F.2d 457, 467
(D.C. Cir. 1991), we would normally be disinclined to accept a
defendant’s post-complaint representation that contradicts a
factual assertion made in the complaint.

     But this is no ordinary case. We deal here with Congress’s
interpretation of its rules—something no court can lightly
disregard. See United States v. Smith, 286 U.S. 6, 33 (1932)
(“[T]he Court must give great weight to [Congress’s] . . .
construction of its own rules . . . .”). The Rulemaking Clause
of Article I, Section 5 of the Constitution “clearly reserves to
each House of the Congress the authority to make its own
rules,” and as we have explained, interpreting a congressional
rule “differently than would the Congress itself” is tantamount
to “making the Rules—a power that the Rulemaking Clause
reserves to each House alone.” United States v. Rostenkowski,
59 F.3d 1291, 1306–07 (D.C. Cir. 1995) (emphasis added).
Accordingly, we accept the House’s interpretation of its own
rules as requiring a religious prayer, thus eliminating any risk
of running afoul of either the Rulemaking Clause or separation-
of-powers principles. See Boehner v. McDermott, 484 F.3d
573, 580 (D.C. Cir. 2007) (en banc) (“We . . . accept the Ethics
Committee’s interpretation of the rules as applied to this case,
and thereby eliminate the concerns mentioned in
Rostenkowski.”). Barker suffers no prejudice as a result of our
acceptance of the House’s position because, as explained
above, rather than disputing that the House interprets its rules
as requiring a religious prayer, he simply argues that the rules
themselves compel no such interpretation. See Appellant’s Br.
23–24 (“Dismissal at this stage was . . . improper because the
court could conclude that the House Rule do[es] not, in fact,
                               21
preclude a nonreligious prayer . . . .”); Reply Br. 7
(acknowledging the existence of “a supposed House
requirement that ‘prayer’ necessarily must implicate a religious
deity” but arguing that prayer can and should be defined more
broadly).

     The question, then, is this: does the House’s decision to
limit the opening prayer to religious prayer fit “within the
tradition long followed in Congress and the state legislatures”?
Town of Greece, 572 U.S. at 577. The answer is yes.

     In Marsh, the Supreme Court took as a given the religious
nature of legislative prayer. In holding that opening the
legislative day with a prayer amounted not to an establishment
of religion but rather to “a tolerable acknowledgment of beliefs
widely held among the people of this country,” the Court
explained that “‘[w]e are a religious people whose institutions
presuppose a Supreme Being.’” 463 U.S. at 792 (alteration in
original) (quoting Zorach v. Clauson, 343 U.S. 306, 313
(1952)); see also id. (“To invoke Divine guidance on a public
body entrusted with making the laws is not, in these
circumstances, an ‘establishment’ of religion or a step toward
establishment . . . .”). Over the dissent’s objection that “prayer
is fundamentally and necessarily religious,” and thus has no
place in the halls of Congress, id. at 810 (Brennan, J.,
dissenting), the Court upheld the practice, describing it as
having “coexisted with the principles of disestablishment and
religious freedom” “[f]rom colonial times through the founding
of the Republic and ever since,” id. at 786.

     The prayer practice at issue in Town of Greece was, at least
in theory, significantly more inclusive than the one in Marsh.
See Town of Greece, 572 U.S. at 571 (“The town at no point
excluded or denied an opportunity to a would-be prayer giver.
Its leaders maintained that a minister or layperson of any
                                22
persuasion, including an atheist, could give the invocation.”).
Yet in that case, too, the Supreme Court recognized legislative
prayer’s religious roots. The Court described Marsh as
“conclud[ing] that legislative prayer, while religious in nature,
has long been understood as compatible with the Establishment
Clause.” Id. at 575 (emphasis added); see also id. at 576 (“That
the First Congress provided for the appointment of chaplains
only days after approving language for the First Amendment
demonstrates that the Framers considered legislative prayer a
benign acknowledgment of religion’s role in society.”
(emphasis added)).

     Marsh and Town of Greece leave no doubt that the
Supreme Court understands our nation’s longstanding
legislative-prayer tradition as one that, because of its “unique
history,” can be both religious and consistent with the
Establishment Clause. Marsh, 463 U.S. at 791. And although
the Court has warned against discriminating among religions
or tolerating a pattern of prayers that proselytize or disparage
certain faiths or beliefs, it has never suggested that legislatures
must allow secular as well as religious prayer. In the sui generis
context of legislative prayer, then, the House does not violate
the Establishment Clause by limiting its opening prayer to
religious prayer.

     If Barker’s complaint rested solely on the contention that
a religious prayer requirement is unconstitutional, we could
stop here. But Barker alleges—and we must accept as true at
this stage of the case—that Conroy excluded him not because
he proposed to give a secular prayer but “because [Barker] is
an atheist.” Compl. ¶ 110. According to Barker, the other
reasons Conroy cited for his exclusion—that Barker no longer
practices the faith in which he was ordained and, more recently,
Barker’s unwillingness to give a religious prayer—are merely
“pretextual.” Id. ¶ 109. Had he not “part[ed] with his religious
                                23
beliefs,” Barker alleges, “he would have been approved to
deliver an invocation, but as a nonreligious officiant with a
valid ordination, he was denied.” Id. ¶ 117 (alterations in
original) (internal quotation marks omitted); see also Oral Arg.
Rec. 55:09–19 (Barker’s counsel: “We have these other prayers
that are nearly identical to the prayer that Mr. Barker wishes to
give. It’s just a question of who he is, an atheist, and that’s why
he was denied.”).

     To resolve this case, however, we need not decide whether
there is a constitutional difference between excluding a would-
be prayer-giver from the guest chaplain program because he is
an atheist and excluding him because he has expressed a desire
to deliver a nonreligious prayer. Even though we accept as true
Barker’s allegation that Conroy rejected him “because he is an
atheist,” Compl. ¶ 110, the House’s requirement that prayers
must be religious nonetheless precludes Barker from doing the
very thing he asks us to order Conroy to allow him to do:
deliver a secular prayer. In other words, even if, as Barker
alleges, he was actually excluded simply for being an atheist,
he is entitled to none of the relief he seeks. We could not order
Conroy to allow Barker to deliver a secular invocation because
the House permissibly limits the opening prayer to religious
prayer. Barker has therefore failed to state a claim for which
relief can be granted.

                               IV.
    For the foregoing reasons, we affirm the district court’s
dismissal of Barker’s Establishment Clause claim.

                                                      So ordered.
