                 FOR PUBLICATION

  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT


JONATHAN C. CAPP; N.C., a minor,          No. 18-55119
by and thru their Guardian ad litem;
J.C., a minor, by and thru their             D.C. No.
Guardian ad litem,                        3:16-cv-02870-
                 Plaintiffs-Appellants,     AJB-MDD

                  v.
                                            OPINION
COUNTY OF SAN DIEGO; KATHY
JACKSON; BOB PROKESCH; JOHANNA
FIRTH; SAN DIEGO HEALTH AND
HUMAN SERVICES AGENCY,
             Defendants-Appellees.

     Appeal from the United States District Court
        for the Southern District of California
     Anthony J. Battaglia, District Judge, Presiding

          Argued and Submitted July 10, 2019
                 Pasadena, California

                  Filed August 30, 2019
2               CAPP V. COUNTY OF SAN DIEGO

    Before: MILAN D. SMITH, JR. and MICHELLE T.
     FRIEDLAND, Circuit Judges, and STANLEY A.
               BASTIAN, * District Judge.

             Opinion by Judge Milan D. Smith, Jr.


                          SUMMARY **


                            Civil Rights

    The panel affirmed in part and reversed in part the
district court’s dismissal of plaintiffs’ claims as
insufficiently pled in an action brought by Jonathan Capp
and his two minor children arising from a child welfare
investigation undertaken by County of San Diego social
workers that allegedly violated plaintiffs’ First, Fourth, and
Fourteenth Amendment rights.

     Plaintiffs asserted, in part, that social workers retaliated
against Capp in violation of the First Amendment after he
questioned abuse allegations against him and criticized the
County. Plaintiffs asserted that defendants placed Capp on
the Child Abuse Central Index and coerced his ex-wife to
file an ex parte custody application.

    The panel first rejected the retaliation claim premised on
the Child Abuse Central Index listing. The panel held that

    *
      The Honorable Stanley A. Bastian, United States District Judge for
the Eastern District of Washington, sitting by designation.
    **
       This summary constitutes no part of the opinion of the court. It
has been prepared by court staff for the convenience of the reader.
              CAPP V. COUNTY OF SAN DIEGO                    3

taking the allegations as a whole, the first amended
complaint did not plausibly allege that Capp was placed on
the Index as intentional retaliation. Focusing on plaintiffs’
allegation that defendant social worker coerced Capp’s
former wife to file the ex parte custody application, the panel
found that pursuant to the liberal pleading standard afforded
pro se litigants, plaintiffs plausibly alleged that Capp
engaged in protected activity, that the alleged retaliation
would objectively have had a chilling effect and that
retaliation was the but-for motive for the social worker’s
actions. Plaintiffs therefore pleaded a plausible First
Amendment retaliation claim. The panel further concluded
that the accused defendant social worker was not entitled to
qualified immunity. The panel held that a reasonable official
would know that taking the serious step of threatening to
terminate a parent’s custody of his children, when the
official would not have taken this step absent her retaliatory
intent, violates the First Amendment.

    The panel held that the district court properly dismissed
plaintiffs’ Fourth Amendment and Fourteenth Amendment
claims, and claims brought pursuant to Monell v.
Department of Social Services, 436 U.S. 658 (1978), which
alleged that defendants interviewed the minor children while
they were at school without Capp’s consent. The panel held
that the first amended complaint contained no facts as to
whether the interviews were conducted without either
parent’s permission, the length of the interviews, or the
specific circumstances of the interviews. Moreover, the
panel held that even if plaintiffs had pleaded a plausible
Fourth Amendment claim, defendants would be entitled to
qualified immunity because the right of minor children to be
free from unconstitutional seizures and interrogations by
social workers had not been clearly established.
4              CAPP V. COUNTY OF SAN DIEGO

    Rejecting the Fourteenth Amendment substantive due
process claim, the panel held that although Capp might have
been subjected to an investigation by the County’s Health
and Human Services Agency, that alone was not cognizable
as a violation of the liberty interest in familial relations. The
panel rejected the Monell claim, concluding that plaintiffs
failed to plead a plausible constitutional violation stemming
from defendants’ interviews with the children. Moreover,
even if plaintiffs had pleaded a plausible Fourth Amendment
claim, the first amended complaint ascribed defendants’
alleged misconduct to official policy in a conclusory fashion
that was insufficient to state a viable claim.


                         COUNSEL

Jonathan Charles Capp (argued), Law Offices of Jonathan C.
Capp, San Diego, California, pro se Plaintiff-Appellant.

Christina Snider (argued), Senior Deputy; Thomas E.
Montgomery, County Counsel; Office of County Counsel,
San Diego, California; for Defendant-Appellee.
              CAPP V. COUNTY OF SAN DIEGO                  5

                        OPINION

M. SMITH, Circuit Judge:

    Plaintiffs Jonathan Capp and his children, N.C. and J.C.,
assert § 1983 and Monell claims against Defendants County
of San Diego (the County); the County’s Health and Human
Services Agency (the Agency); and Kathy Jackson, Bob
Prokesch, and Johanna Firth, social workers employed by
the Agency. The action stems from a child welfare
investigation undertaken by Defendants that allegedly
violated Plaintiffs’ First, Fourth, and Fourteenth
Amendment rights.

    The district court dismissed all of Plaintiffs’ claims as
insufficiently pleaded or barred by qualified immunity. We
agree that Plaintiffs’ first amended complaint (FAC) fails to
plausibly allege Fourth Amendment, Fourteenth
Amendment, and Monell claims. We also conclude,
however, that Plaintiffs plead a viable First Amendment
retaliation claim, and that Defendants are not entitled to
qualified immunity on this claim.

  FACTUAL AND PROCEDURAL BACKGROUND

I. Factual Background

    The facts as presented are derived from Plaintiffs’ FAC.
For purposes of our analysis, we accept the allegations as
true. See Karam v. City of Burbank, 352 F.3d 1188, 1192
(9th Cir. 2003).

    Capp is the father of two minor children, N.C. (age 11 at
the time Plaintiffs filed their FAC) and J.C. (age 9), whose
legal custody he shares with their mother, Debora. Capp and
6             CAPP V. COUNTY OF SAN DIEGO

Debora were in the midst of divorce proceedings at the time
of Defendants’ investigation.

    On August 13, 2015, the Agency received a referral
alleging that N.C. and J.C. “may be at-risk of General
Neglect, Severe Neglect, and Emotional Abuse by Jonathan
Capp.” Firth, a social worker, informed Capp that “she
wished to speak with him regarding his children and
referenced a substance abuse problem”; the two arranged a
meeting for August 26. During that meeting, Capp learned
that Firth had interviewed N.C. and J.C. at their elementary
school “without [Capp’s] consent.”          Although Capp
repeatedly asked for clarification regarding the allegations
against him, Firth was evasive and “unilaterally terminated
the interview.”

    That same day, Capp sent a letter to the Agency, calling
the interview “Kafkaesque” and deeming the “offensive
allegations (whatever they may be) [] bogus and extremely
offensive.” The letter chastised Firth for “fle[eing]” the
meeting, and for “interview[ing Capp’s] children without
[his] consent.” Capp concluded, “In any event, be in no
doubt that if you continue on your unlawful and
unconstitutional course I will take this matter even further.”

    Soon after, Capp learned that Debora’s attorney “had
instructed her client to withhold custody of the children
pursuant to ‘instructions from [the Agency],’” which had
apparently told Debora to “apply ex-parte to the San Diego
family court . . . to take custody from [Capp].” Indeed, a
declaration from Debora filed with the application read in
part,

       Firth gave me a letter . . . advising me not to
       force our children to visit with their father. It
       was suggested strongly to me that I seek legal
                CAPP V. COUNTY OF SAN DIEGO                         7

        action immediately to keep our children safe.
        They have been indicating to me that they do
        not want to see their father, who is often
        angry with them, yells at them, calls them
        names (such as “spoiled” and “b—”), and
        scares them.

Subsequently, the family court “denied the application and
rebuked [the Agency].” Capp spoke with Jackson, Firth’s
supervisor, who assured him that she “would make sure that
all appropriate procedures would be followed” and that “the
case would be closed.” Prokesch later interviewed Capp and
“could not in any way articulate any serious (or even
significant or any) allegations against [him],” though
Prokesch did mention an allegation that Capp “may have
driven the children in a car whilst under the influence.”
Eventually, Jackson, Firth, and Prokesch signed a letter to
the court indicating that the evidence against Capp was
“inconclusive.” The Agency then closed the referral.

    The closing of the referral notwithstanding, Capp later
received a letter from the Agency informing him that “the
allegations of abuse or severe neglect” were, in fact,
“substantiated,” and that Capp had consequently been placed
on the Child Abuse Central Index (CACI). 1 After Capp
complained to Jackson and others, another employee of the
Agency allegedly “confirmed again that he was on the CACI
register but that she would recommend that he be taken off.”

    1
      The CACI is an index of child abuse maintained pursuant to the
California Child Abuse and Neglect Reporting Act, which requires that
agencies “forward to the Department of Justice a report in writing of
every case it investigates of known or suspected child abuse or severe
neglect that is determined to be substantiated.” Cal. Penal Code
§§ 11164, 11169–70.
8              CAPP V. COUNTY OF SAN DIEGO

Capp was later informed that “due to a clerical or
administrative error or issue,” he “had not been placed on the
CACI at all,” despite his having been informed otherwise.
He eventually received a letter from the Agency confirming
that his “name has not been listed on the [CACI].”

II. Procedural History

   Plaintiffs filed their initial complaint in November 2016.
The district court granted Defendants’ first motion to dismiss
with leave to amend, and Plaintiffs subsequently filed the
FAC.

    Plaintiffs’ § 1983 claim asserts in part that Defendants
retaliated against Capp in violation of the First Amendment.
They allege that after Capp exercised his First Amendment
rights by questioning the abuse allegations against him and
the legal basis for Firth’s interviews, and then by lodging
various criticisms against the County, Firth “coerced”
Debora to file the ex parte application and, together with
Jackson and Prokesch, placed him on the CACI. They also
allege that these actions, and the investigation generally,
violated Capp’s Fourteenth Amendment right to familial
association, and that the interviews with the children
violated their Fourth Amendment right to be free from
unreasonable seizure. Plaintiffs also assert a cause of action
pursuant to Monell v. Department of Social Services,
436 U.S. 658 (1978), based on the County’s alleged “policy
of detaining and interviewing children without exigent
circumstances . . . , court order or consent of their parent,” in
violation of the Fourth Amendment.

   Defendants again moved to dismiss, and the district court
granted the motion as to all causes of action except the First
Amendment retaliation claim. As to this remaining claim,
the district court concluded that, “[w]hile there is no
              CAPP V. COUNTY OF SAN DIEGO                  9

precedent directly on point that allows First Amendment
retaliation claims to go forward against social workers,”
Firth and Prokesch could not claim qualified immunity
because “[r]easonable social workers in Defendants’
positions know or should know that baselessly taking action
that could lead to a child being wrongfully removed from its
parents would [run] afoul of the First Amendment.”

    Defendants then filed a motion for reconsideration,
contending that the district court’s qualified immunity
analysis had been flawed. The court agreed, concluding that
“there was [] no clearly established law at the time denoting
defendants’ specific actions in this case as unlawful,” and
therefore that “qualified immunity [] attache[d]” to both
Firth and Prokesch. All claims having been dismissed, the
district court entered final judgment, and this timely appeal
followed.

   JURISDICTION AND STANDARD OF REVIEW

   We have jurisdiction pursuant to 28 U.S.C. § 1291.

    “We review de novo a district court’s dismissal of a
complaint under [Federal Rule of Civil Procedure] 12(b)(6)
for failure to state a claim.” Applied Underwriters, Inc. v.
Lichtenegger, 913 F.3d 884, 890 (9th Cir. 2019) (quoting
Starr v. Baca, 652 F.3d 1202, 1205 (9th Cir. 2011)). “When
ruling on a motion to dismiss, we accept all factual
allegations in the complaint as true and construe the
pleadings in the light most favorable to the nonmoving
party.” Knievel v. ESPN, 393 F.3d 1068, 1072 (9th Cir.
2005). The allegations “must ‘plausibly give rise to an
entitlement to relief.’” Dougherty v. City of Covina,
654 F.3d 892, 897 (9th Cir. 2011) (quoting Ashcroft v. Iqbal,
556 U.S. 662, 679 (2009)). We have emphasized that pro se
pleadings, such as the FAC in this case, are to be liberally
10             CAPP V. COUNTY OF SAN DIEGO

construed on a motion to dismiss. See, e.g., Thompson v.
Davis, 295 F.3d 890, 895 (9th Cir. 2002).

    We review a grant of qualified immunity de novo. Entler
v. Gregoire, 872 F.3d 1031, 1038 (9th Cir. 2017).

                         ANALYSIS

I. First Amendment Retaliation Claim

    After    considering      Defendants’    motion      for
reconsideration, the district court concluded that qualified
immunity attaches to this claim.

    “The doctrine of qualified immunity protects
government officials ‘from liability for civil damages insofar
as their conduct does not violate clearly established statutory
or constitutional rights of which a reasonable person would
have known.’” Pearson v. Callahan, 555 U.S. 223, 231
(2009) (quoting Harlow v. Fitzgerald, 457 U.S. 800, 818
(1982)). It “gives government officials breathing room to
make reasonable but mistaken judgments about open legal
questions,” and, “[w]hen properly applied, [] protects ‘all but
the plainly incompetent or those who knowingly violate the
law.’” Ashcroft v. al-Kidd, 563 U.S. 731, 743 (2011)
(quoting Malley v. Briggs, 475 U.S. 335, 341 (1986)).

     The Supreme Court has articulated a discretionary

        two-step sequence for resolving government
        officials’ qualified immunity claims. First, a
        court must decide whether the facts that a
        plaintiff has alleged or shown make out a
        violation of a constitutional right. Second, if
        the plaintiff has satisfied this first step, the
        court must decide whether the right at issue
              CAPP V. COUNTY OF SAN DIEGO                  11

       was “clearly established” at the time of
       defendant’s alleged misconduct.

Pearson, 555 U.S. at 232 (citations omitted) (quoting
Saucier v. Katz, 533 U.S. 194, 201 (2001)). Accordingly,
we first consider whether Plaintiffs plausibly plead a
violation of a constitutional right, before deciding whether
that right was clearly established.

       A. Violation of a Constitutional Right

    To state a First Amendment retaliation claim, a plaintiff
must plausibly allege “that (1) he was engaged in a
constitutionally protected activity, (2) the defendant’s
actions would chill a person of ordinary firmness from
continuing to engage in the protected activity and (3) the
protected activity was a substantial or motivating factor in
the defendant’s conduct.” O’Brien v. Welty, 818 F.3d 920,
932 (9th Cir. 2016) (quoting Pinard v. Clatskanie Sch. Dist.
6J, 467 F.3d 755, 770 (9th Cir. 2006)). To ultimately
“prevail on such a claim, a plaintiff must establish a ‘causal
connection’ between the government defendant’s
‘retaliatory animus’ and the plaintiff’s ‘subsequent injury.’”
Nieves v. Bartlett, 139 S. Ct. 1715, 1722 (2019) (quoting
Hartman v. Moore, 547 U.S. 250, 259 (2006)). Specifically,
a plaintiff must show that the defendant’s retaliatory animus
was “a ‘but-for’ cause, meaning that the adverse action
against the plaintiff would not have been taken absent the
retaliatory motive.” Id. (quoting Hartman, 547 U.S. at 260).

    Plaintiffs premise their First Amendment retaliation
claim on two allegedly retaliatory actions: (1) Firth’s
coercing Debora to file the ex parte custody application, and
(2) Firth’s, Prokesch’s, and Jackson’s placing Capp on the
CACI.
12               CAPP V. COUNTY OF SAN DIEGO

     At the outset, we reject Plaintiffs’ retaliation claim
premised on the CACI listing. In ruling on Defendants’
motion to dismiss, the district court concluded that the FAC
did not actually plead that Capp was ever placed on the
CACI. We agree that, taking the allegations as a whole, the
FAC does not plausibly allege that Capp was placed on the
CACI as intentional retaliation. According to the FAC,
Capp was twice informed that he had never been placed on
the CACI, so the more plausible inference to draw from the
FAC is that Capp was either never listed on the CACI, or
that he was briefly and accidentally listed and then promptly
removed. Thus, even if Capp might have “reasonably
believed that he had been placed on the register,” this does
not give rise to Plaintiffs’ retaliation claim, since such a
belief is distinct from actual, intentional placement on the
register. Accordingly, even under the liberal pleading
standards afforded to the FAC, we cannot accept the CACI
listing as a plausible foundation for Plaintiffs’ First
Amendment retaliation claim.

    We therefore focus only on Plaintiffs’ allegation that
Firth coerced Debora to file the ex parte custody application
in retaliation for Capp’s criticism. 2




     2
       Although the district court apparently interpreted the ex parte
application allegation as being directed against both Firth and Prokesch,
the FAC does not clearly attribute this alleged misconduct to Prokesch.
Instead, it reads, “At least Defendant [Firth] coerced the children’s
mother to file an ex-parte application . . . .” Given this language, and in
light of the allegations contained elsewhere in the complaint, we construe
this specific claim as being directed against Firth only, and not against
Prokesch or any other Defendant.
              CAPP V. COUNTY OF SAN DIEGO                   13

       i. Constitutionally Protected Activity

    The first O’Brien element is satisfied here. It is well
settled that the activity for which Capp was allegedly
retaliated against—voicing criticism of the Agency’s
conduct—is constitutionally protected. See Hartman,
547 U.S. at 256 (“[T]he law is settled that as a general matter
the First Amendment prohibits government officials from
subjecting an individual to retaliatory actions . . . for
speaking out.”); Ford v. City of Yakima, 706 F.3d 1188,
1192–93 (9th Cir. 2013) (per curiam) (“While an
individual’s critical comments may be ‘provocative and
challenging,’ they are ‘nevertheless protected against
censorship or punishment, unless shown likely to produce a
clear and present danger of a serious substantive evil that
rises far above public inconvenience, annoyance, or unrest.’”
(quoting City of Houston v. Hill, 482 U.S. 451, 461 (1987))),
abrogated on other grounds by Nieves, 139 S. Ct. 1715.

       ii. Chilling Effect

    Defendants correctly observe that Capp was not muzzled
by the ex parte custody application. The FAC alleges that
“[u]pon receiving the ex-parte application,” Capp
“immediately contacted his State Assembly member . . . and
his local San Diego county supervisor . . . to protest what
was happening,” and “as a result . . . was advised to contact”
supervisor Jackson. Clearly, Capp was not chilled by the
alleged retaliation; he continued, and even escalated, his
protected activity.

    Our inquiry, however, is not whether Defendants’
actions actually chilled Capp, but rather whether the alleged
retaliation “would chill a person of ordinary firmness from
continuing to engage in the protected activity.” O’Brien,
818 F.3d at 932 (emphasis added) (quoting Pinard, 467 F.3d
14             CAPP V. COUNTY OF SAN DIEGO

at 770); see also id. at 933 (“The test is generic and objective.
Whether O’Brien himself was, or would have been, chilled
is not the test.”); Mendocino Envtl. Ctr. v. Mendocino
County, 192 F.3d 1283, 1300 (9th Cir. 1999) (“Because it
would be unjust to allow a defendant to escape liability for a
First Amendment violation merely because an unusually
determined plaintiff persists in his protected activity, we
conclude that the proper inquiry asks ‘whether an official’s
acts would chill or silence a person of ordinary firmness
from future First Amendment activities.’” (quoting
Crawford-El v. Britton, 93 F.3d 813, 826 (D.C. Cir. 1996))).
The threat of losing custody of one’s children is a severe
consequence that would chill the average person from
voicing criticism of official conduct.              Accordingly,
notwithstanding the fact that Capp himself was not chilled
by Firth’s conduct, we conclude that the alleged retaliation
would objectively have had a chilling effect.

        iii.    Substantial or Motivating Factor

    The closest issue before us is whether Plaintiffs plausibly
plead that Capp’s criticism “was a substantial or motivating
factor” in Firth’s decision to instruct Debora to seek custody
of N.C. and J.C. O’Brien, 818 F.3d at 932 (quoting Pinard,
467 F.3d at 770).

    The FAC alleges that Firth “coerced [Debora] to file an
ex-parte application in an attempt to strip [Capp] of custody
of the children,” and that this act was “purely motivated by
[Defendants’] desire to retaliate against” Capp. Specifically,
Plaintiffs appear to allege that Firth coerced Debora into
entering a safety plan—which provided that Debora would
seek sole custody—by threatening to “instigate juvenile
                 CAPP V. COUNTY OF SAN DIEGO                          15

proceedings.” 3 Plaintiffs further allege that Defendants
“would not have otherwise acted as such but for the activity
of [Capp] as described” in the complaint because “there was
no objective basis to . . . strip him of custody.”

    Defendants argue that Plaintiffs “offer[] nothing but
suspicion and speculation to support [their] allegations that
the social workers’ actions were motivated by retaliatory
animus.” But we have recognized that such speculation is
hardly unusual in retaliation cases. See Watison v. Carter,
668 F.3d 1108, 1114 (9th Cir. 2012) (“Because direct
evidence of retaliatory intent rarely can be pleaded in a
complaint, allegation of a chronology of events from which
retaliation can be inferred is sufficient to survive
dismissal.”).

    More problematic to Plaintiffs’ claim is the Supreme
Court’s admonition that an allegation is not plausible where
there is an “obvious alternative explanation” for alleged
misconduct. Iqbal, 556 U.S. at 682 (quoting Bell Atl. Corp.
v. Twombly, 550 U.S. 544, 567 (2007)). Here, in its
reconsideration order, the district court concluded that

         [i]t is not entirely clear from Capp’s
         complaint that defendants’ motives were to
         punish Capp for exercising his first
         amendment rights. . . . A social worker’s job
         is to make recommendations when they fear
         a minor might be in danger—thus it appears

    3
      The safety plan attached to the FAC stated that its purpose “is to
allow children to remain in their homes pending completion of the
investigation by Child Welfare Services (CWS) when one or more Safety
Factors are identified.” It specified that “Mom plans to keep the children
in her care until her Family Court attorney can file for an emergency
custody order next week.”
16             CAPP V. COUNTY OF SAN DIEGO

       to this Court that Firth may have been simply
       doing her job.

    We recognize that social workers like Firth have a legal
obligation to investigate allegations of child abuse. See, e.g.,
Cal. Welf. & Inst. Code § 328 (requiring a social worker to
“immediately make any investigation he or she deems
necessary” if child abuse is suspected); cf. Mann v. County
of San Diego, 907 F.3d 1154, 1156 (9th Cir. 2018)
(recognizing “the state’s interest in protecting children from
abusive or neglectful conditions”).           Here, Debora’s
declaration accompanying her ex parte application, which
was included in the FAC, stated that Capp’s children “ha[d]
been indicating . . . that they do not want to see their father,
who is often angry with them, yells at them, calls them
names . . . and scares them.” Defendants contend that,
“[b]ased on these statements from Debora alone, it was
reasonable for Firth to encourage Debora to seek to limit
Capp’s custody.”

    It is true that the allegations about Debora’s concerns
lead to the inference, which the district court made, that Firth
was at least partially motivated by her legal obligations to
protect the children. It is also true that if this were Firth’s
only motive, Plaintiffs’ First Amendment retaliation claim
would necessarily fail because the third O’Brien element
would not be satisfied.

     And yet, we conclude that the mere existence of a
legitimate motive, supported though it might be by the FAC,
is insufficient to mandate dismissal. If Firth would not have
made the recommendation absent retaliatory animus, there
could still be a viable retaliation claim. See O’Brien,
818 F.3d at 936 (“We have previously made it clear that
there is a right to be free from retaliation even if a non-
               CAPP V. COUNTY OF SAN DIEGO                   17

retaliatory justification exists for the defendants’ action.”).
And Plaintiffs have plausibly alleged that retaliatory animus
was a but-for cause of Firth’s actions.

    We find instructive the Supreme Court’s decision in
Nieves. There, the Court held that plaintiffs bringing “First
Amendment retaliatory arrest claims” must generally “plead
and prove the absence of probable cause.” Nieves, 139 S.
Ct. at 1723. In “retaliatory arrest cases,” the Court
explained, there is “a tenuous causal connection between the
defendant’s alleged animus and the plaintiff’s injury.” Id.
(quoting Reichle v. Howards, 566 U.S. 658, 668 (2012)).
“[P]rotected speech is often a ‘wholly legitimate
consideration’ for officers when deciding whether to make
an arrest,” given that “a suspect’s speech may convey vital
information” like whether the suspect is willing to cooperate.
Id. at 1724 (quoting Reichle, 566 U.S. at 668). If the plaintiff
demonstrates that the arresting officer lacked probable
cause, that showing bridges the causal gap by “reinforc[ing]
the retaliation evidence and show[ing] that retaliation was
the but-for basis” of the official’s action. Id. at 1723
(quoting Hartman, 547 U.S. at 261).

    But the Court carved out an exception to the “no-
probable-cause requirement” in retaliatory arrest cases. Id.
at 1727. That requirement does “not apply when a plaintiff
presents objective evidence that he was arrested when
otherwise similarly situated individuals not engaged in the
same sort of protected speech had not been.” Id. For
example, “[i]f an individual who has been vocally
complaining about police conduct is arrested for
jaywalking”—an offense that “rarely results in arrest”—“it
would seem insufficiently protective of First Amendment
rights to dismiss the individual’s retaliatory arrest claim on
the ground that there was undoubted probable cause for the
18               CAPP V. COUNTY OF SAN DIEGO

arrest.” Id. A plaintiff who shows differential treatment
“addresses [the] causal concern by helping to establish that
‘non-retaliatory grounds [we]re in fact insufficient to
provoke the adverse consequences.’” Id. (second alteration
in original) (quoting Hartman, 547 U.S. at 256).

    In this case, Plaintiffs have pleaded both a lack of any
substantiated concern for the children’s safety (which may
well be the equivalent of probable cause in this context) 4 and
differential treatment. These allegations together support the
inference that Firth was motivated by retaliatory animus.

    Plaintiffs plead that Debora’s allegations—that the
children “do not want to see their father, who is often angry
with them, yells at them, calls them names . . . and scares
them”—were not “serious” enough to warrant Firth’s
instructing Debora to seek sole custody. The FAC also
pleads that the allegations about Capp were not

     4
       We have not previously decided, and do not decide in this case,
what the Constitution requires before a social worker may coerce a
parent into entering a safety plan—as Plaintiffs appear to allege Firth did
here. The two circuits that have addressed this question have held that
social workers must have “reasonable suspicion” of abuse. Hernandez
ex rel. Hernandez v. Foster, 657 F.3d 463, 482 (7th Cir. 2011) (requiring
“‘some definite and articulable evidence giving rise to a reasonable
suspicion’ of past or imminent danger of abuse” (quoting Brokaw v.
Mercer County, 235 F.3d 1000, 1019 (7th Cir. 2000))); Croft v.
Westmoreland Cty. Children & Youth Servs., 103 F.3d 1123, 1126 (3d
Cir. 1997) (requiring “an objectively reasonable suspicion of abuse”). If
this is the correct standard, then a social worker would likely need to
corroborate allegations of abuse to satisfy it. Cf. United States v.
Williams, 846 F.3d 303, 308–09 (9th Cir. 2016) (holding that officers
had reasonable suspicion when an identified tipster’s information was
“verified . . . through independent observation”); United States v.
Rowland, 464 F.3d 899, 907–08 (9th Cir. 2006) (holding that agents had
reasonable suspicion when they met with the informant and
“corroborated the informant’s tip”).
                 CAPP V. COUNTY OF SAN DIEGO                            19

substantiated. Plaintiffs allege that Prokesch “could not in
any way articulate any serious (or even significant or any)
allegations against [Capp],” that a judge declined to modify
Capp’s custody arrangement in response to Debora’s
allegations that their children were scared of Capp, and that
a judge “confirmed that [the County] had reported to the
court that the emotional abuse claims made against [Capp]
were inconclusive.” Accepting these allegations as true, we
infer from the FAC that retaliatory rather than legitimate
motives drove Firth’s actions.

    Plaintiffs further allege that Firth only tried to modify
Capp’s custody, even though Debora had engaged in unsafe
behavior around the children. The FAC states that Firth
instructed Debora to seek sole custody, “even though
[Debora] was, at that very same time, on probation due to
her recently driving under the influence of alcohol with J.C.
and N.C. in the car[,] for which [Debora] was charged with
child endangerment as well as a D.U.I.” The FAC
additionally alleges that a “family law judge came within a
hair’s breadth of stripping [Debora] of her physical
custody.” “[C]onstru[ing] the complaint in the light most
favorable” to Plaintiffs, Doe v. United States, 419 F.3d 1058,
1062 (9th Cir. 2005), the FAC pleads that even though there
was reason to be concerned about both Capp and Debora,
Firth only ever took action against the parent who had
decided to exercise his First Amendment rights.

   We acknowledge that this is likely to be a very close
case. 5 At summary judgment or at trial, Defendants could
well marshal evidence that Firth and her colleagues were

    5
      To underscore this point, we observe that the district court initially
concluded that Plaintiffs pleaded a viable First Amendment retaliation
claim, before reconsidering its position.
20               CAPP V. COUNTY OF SAN DIEGO

motivated primarily by their legal obligation to investigate
allegations of child abuse, and would have made the custody
recommendation for that reason alone. See Karam, 352 F.3d
at 1194 (rejecting First Amendment retaliation claim where
plaintiff’s “speculation as to [] improper motive does not rise
to the level of evidence sufficient to survive summary
judgment”). But Plaintiffs plead that Defendants, Firth
included, “were purely motivated by their desire to retaliate
against” Capp, acted “without proper reason or authority”
and “without reasonable probable cause,” and “ma[de] false
and misleading statements to retaliate against [Capp] and in
order to unduly influence and threaten [Debora] to file an
application with the Family court.” Taking these allegations
in the light most favorable to Plaintiffs, and emphasizing the
liberal pleading standard afforded to pro se litigants, we
conclude that Plaintiffs have plausibly alleged that
retaliation was the but-for motive for Firth’s actions.
Plaintiffs therefore plead a plausible First Amendment
retaliation claim. 6

     B. Clearly Established

     Having determined that Plaintiffs plead a plausible First
Amendment retaliation claim, we now move to the second
prong of the qualified immunity analysis: whether “the right
at issue was ‘clearly established’ at the time of defendant’s
alleged misconduct.” Pearson, 555 U.S. at 232 (quoting

     6
       Our conclusion that Plaintiffs have plausibly alleged but-for
causation should not be read as disturbing our court’s prior cases holding
that plaintiffs need only plausibly allege that retaliatory animus was a
substantial or motivating factor to state a First Amendment retaliation
claim that survives a motion to dismiss. See, e.g., The Koala v. Khosla,
931 F.3d 887, 905 (9th Cir. 2019); Ariz. Students’ Ass’n v. Ariz. Bd. of
Regents, 824 F.3d 858, 867 (9th Cir. 2016); O’Brien, 818 F.3d at 932,
935–36.
                 CAPP V. COUNTY OF SAN DIEGO                            21

Saucier, 533 U.S. at 201). We conclude that Plaintiffs have
sufficiently pleaded a violation of their clearly established
First Amendment rights, and that Firth is therefore not
entitled to qualified immunity.

    “[F]or a right to be clearly established, existing
precedent must have placed the statutory or constitutional
question beyond debate,” though there need not be “a case
directly on point.” Kisela v. Hughes, 138 S. Ct. 1148, 1152
(2018) (per curiam) (quoting White v. Pauly, 137 S. Ct. 548,
551 (2017) (per curiam)); see also White, 137 S. Ct. at 552
(“Today, it is again necessary to reiterate the longstanding
principle that ‘clearly established law’ should not be defined
‘at a high level of generality.’” (quoting al-Kidd, 563 U.S.
at 742)); Reese v. County of Sacramento, 888 F.3d 1030,
1038–39 (9th Cir. 2018) (noting that while we “do not
demand a case with ‘materially similar’ factual
circumstances or even facts closely analogous to [plaintiff’s]
case,” existing caselaw must “demonstrate that the contours
of [the] right were sufficiently clear such that ‘any
reasonable official in [his] shoes would have understood that
he was violating it’” (third alteration in original) (first
quoting Hope v. Pelzer, 536 U.S. 730, 741 (2002); and then
quoting City and County of San Francisco v. Sheehan,
135 S. Ct. 1765, 1774 (2015))). 7



    7
       Plaintiffs suggest that Kisela, White, and Reese are inapplicable
here because they involved excessive force by police officers in violation
of the Fourth Amendment. But we have applied the general principles
of qualified immunity that these cases articulated in a variety of contexts.
See, e.g., Hoch v. Sanzberro, 723 F. App’x 513, 514 (9th Cir. 2018)
(psychiatric technician sued for search and seizure); Daniels Sharpsmart,
Inc. v. Smith, 889 F.3d 608, 617–18 (9th Cir. 2018) (state Department of
Health officials sued for violation of Commerce Clause); Reynolds v.
22              CAPP V. COUNTY OF SAN DIEGO

    Plaintiffs contend that the law clearly establishes a right
to be free of “intentional and calculated acts of retaliation
[by a government actor], with the precise details of the
retaliatory acts being of secondary importance.” We agree
that this is the appropriate level of generality for defining the
relevant legal rule. See Anderson v. Creighton, 483 U.S.
635, 639 (1987).

    Defendants argue that there is no clearly established right
in this case because no precedent involves a social worker’s
“recommend[ation] that an ex-wife seek temporary sole
custody of her children.” But we have made clear that “[t]he
precise nature of the retaliation is not critical to the inquiry
in First Amendment retaliation cases.” Coszalter v. City of
Salem, 320 F.3d 968, 974 (9th Cir. 2003). What matters “is
whether the state ha[s] taken ‘action designed to retaliate
against and chill political expression,’” not the particular
kind of action that the state has taken in retaliation. Id. at 975
(quoting Thomas v. Carpenter, 881 F.2d 828, 829 (9th Cir.
1989)).

    In holding that Plaintiffs plead a plausible retaliation
claim, we already determined that the threat of losing
custody of one’s children would ordinarily chill First
Amendment activity. See Mulligan v. Nichols, 835 F.3d 983,
989 n.5 (9th Cir. 2016) (recognizing that “[i]nformal
measures, such as ‘the threat of invoking legal sanctions and
other means of coercion, persuasion, and intimidation,’ can
violate the First Amendment” (alteration in original)
(quoting White v. Lee, 227 F.3d 1214, 1228 (9th Cir. 2000))).
It was clear at the time Firth acted that government officials
were prohibited from taking retaliatory actions that would be

Bryson, 716 F. App’x 668, 668–69 (9th Cir. 2018) (social workers sued
for removal of child).
               CAPP V. COUNTY OF SAN DIEGO                   23

expected to chill First Amendment activity. See, e.g.,
O’Brien, 818 F.3d at 936 (framing the relevant right as the
“right to be free from retaliation,” rather than the right to be
free from the particularly retaliatory act that occurred, and
holding that the right was clearly established).

    Accordingly, because Plaintiffs have plausibly alleged
that retaliatory animus was the but-for cause of Firth’s
conduct, Firth is not entitled to qualified immunity. The
right to be free from government action that would not have
occurred absent such retaliatory animus is clearly
established. Cf. Daugherty v. Sheer, 891 F.3d 386, 391
(D.C. Cir. 2018) (holding that there is no “clearly established
right to be free from [government] action where retaliatory
motive . . . was not plausibly alleged to be the but-for cause
of the [action]”). As we stated in O’Brien, “[r]etaliation for
engaging in protected speech has long been prohibited by the
First Amendment.” 818 F.3d at 936; see also Nieves, 139 S.
Ct. at 1722 (“‘[A]s a general matter the First Amendment
prohibits government officials from subjecting an individual
to retaliatory actions’ for engaging in protected speech.”
(alteration in original) (quoting Hartman, 547 U.S. at 256)).
A reasonable official would know that taking the serious step
of threatening to terminate a parent’s custody of his children,
when the official would not have taken this step absent her
retaliatory intent, violates the First Amendment.

    Although we conclude at this early stage of the litigation
that Firth is not entitled to qualified immunity, that does not
necessarily mean that this case will progress to trial. “Once
an evidentiary record has been developed through discovery,
defendants will be free to move for summary judgment
based on qualified immunity.” O’Brien, 818 F.3d at 936.
24            CAPP V. COUNTY OF SAN DIEGO

II. Other Claims

    We conclude that the district court properly dismissed
Plaintiffs’ Fourth Amendment, Fourteenth Amendment, and
Monell claims.

     A. Fourth Amendment

   Plaintiffs assert that Defendants violated their Fourth and
Fourteenth Amendment rights based on the interviews of
N.C. and J.C. while they were at school.

    “A ‘seizure’ triggering the Fourth Amendment’s
protections occurs only when government actors have, ‘by
means of physical force or show of authority, . . . in some
way restrained the liberty of a citizen.’” Graham v. Connor,
490 U.S. 386, 395 n.10 (1989) (quoting Terry v. Ohio,
392 U.S. 1, 19 n.16 (1968)). The FAC provides insufficient
allegations to support Plaintiffs’ contention that the
interviews of N.C. and J.C. violated the Fourth Amendment.
It pleads that “the children were interviewed without the
consent of either of their parents, without the presence of
exigent circumstances, and without a prior judicial order or
warrant,” and includes the conclusory assertion that “[t]he
children were seized in that they were taken from their class
and had no choice but to comply with the demand that they
be detained and interviewed.” However, it contains no facts
as to whether the interviews were conducted without either
parent’s permission (and, here, their mother might have
consented), the length of the interviews, or the specific
circumstances of the interviews. Absent such allegations,
we cannot conclude that N.C. and J.C. were impermissibly
restrained.

  Even if Plaintiffs had pleaded a plausible Fourth
Amendment claim, Defendants would be entitled to
              CAPP V. COUNTY OF SAN DIEGO                  25

qualified immunity because the right of minor children to be
free from unconstitutional seizures and interrogations by
social workers has not been clearly established. Plaintiffs
rely on Greene v. Camreta, in which we held that social
workers’ seizure and interrogation of a child, absent a
warrant, a court order, exigent circumstances, or parental
consent, was unconstitutional. See 588 F.3d 1011, 1030 (9th
Cir. 2009). The Supreme Court, however, vacated this
portion of Greene, and in so doing expressly acknowledged
that “[t]he point of vacatur is to prevent an unreviewable
decision ‘from spawning any legal consequences,’ so that no
party is harmed by what we have called a ‘preliminary’
adjudication.” Camreta v. Greene, 563 U.S. 692, 713 (2011)
(quoting United States v. Munsingwear, Inc., 340 U.S. 36,
40–41 (1950)); see also id. (noting that “a constitutional
ruling in a qualified immunity case is a legally consequential
decision” and hence that “[v]acatur [] rightly ‘strips the
decision below of its binding effect’” (quoting Deakins v.
Monaghan, 484 U.S. 193, 200 (1988))).

    Additionally, although we determined in Greene that a
Fourth Amendment violation occurred in that case, we
nevertheless held that the social worker defendants had
qualified immunity because “our precedent did not clearly
establish that the in-school seizure of a student suspected of
being the victim of child sexual abuse can be subject to
traditional Fourth Amendment protections.” 588 F.3d
at 1033. The Supreme Court specifically “le[ft] untouched
the Court of Appeals’ ruling on qualified immunity and its
corresponding dismissal of [plaintiff’s] claim.” Camreta,
563 U.S. at 714 n.11. We are thus bound by Greene to
conclude that the Fourth Amendment right Plaintiffs seek to
vindicate was not clearly established.
26               CAPP V. COUNTY OF SAN DIEGO

     B. Fourteenth Amendment

    The basis for Plaintiffs’ Fourteenth Amendment claim is
the same as their First Amendment retaliation claim:
Defendants’ alleged retaliatory actions, which Plaintiffs
claim violated their “fundamental rights to familial
association and due process.”

    “To establish a substantive due process claim, a plaintiff
must, as a threshold matter, show a government deprivation
of life, liberty, or property.” Nunez v. City of Los Angeles,
147 F.3d 867, 871 (9th Cir. 1998). Here, Plaintiffs have not
pleaded that Capp experienced such a deprivation. We have
recognized that “[o]fficial conduct that ‘shocks the
conscience’ in depriving parents of [a relationship with their
children] is cognizable as a violation of due process,”
Wilkinson v. Torres, 610 F.3d 546, 554 (9th Cir. 2010)
(quoting Porter v. Osborn, 546 F.3d 1131, 1137 (9th Cir.
2008)), but Plaintiffs do not allege that Capp actually lost
custody of his children as a result of Defendants’ alleged
misconduct. 8 Capp might have been subjected to an
investigation by the Agency, but that alone is not cognizable
as a violation of the liberty interest in familial relations. Cf.
Woodrum v. Woodward County, 866 F.2d 1121, 1124 (9th
Cir. 1989) (“A parent’s interest in the custody and care of his
or her children is a constitutionally protected liberty interest,
such that due process must be afforded prior to a termination
of parental status.” (emphasis added)). 9

    8
      Quite the contrary, they claim that, after Debora filed the ex parte
application, the family court “denied the application and rebuked [the
Agency].”
     9
     Plaintiffs also premise their Fourteenth Amendment claim on
Capp’s purported inclusion on the CACI, but as explained in our
                 CAPP V. COUNTY OF SAN DIEGO                          27

    C. Monell

    Finally, Plaintiffs assert a Monell claim, based on the
allegedly unconstitutional interviews of N.C. and J.C. 10

    As discussed above, we conclude that Plaintiffs failed to
plead a plausible constitutional violation stemming from
Defendants’ interviews with the children. Plaintiffs’ Monell
claim therefore fails. See Plumeau v. Sch. Dist. No. 40,
130 F.3d 432, 438 (9th Cir. 1997) (listing deprivation of a
constitutional right as an element of § 1983 municipal
liability). Moreover, even if Plaintiffs had pleaded a
plausible Fourth Amendment claim, the FAC ascribes
Defendants’ alleged misconduct to official policy in a
conclusory fashion that is insufficient to state a viable claim.
See Dougherty, 654 F.3d at 900 (dismissing “Monell and
supervisory liability claims [that] lack[ed] any factual
allegations that would separate them from the ‘formulaic
recitation of a cause of action’s elements’ deemed
insufficient by Twombly” (quoting Twombly, 550 U.S. at
555)).



discussion of the First Amendment retaliation claim, we conclude that
the FAC fails to plausibly plead that Capp was listed due to retaliatory
intent.
     10
        Although the FAC pleads that municipal “policies were the cause
of violation of Plaintiffs’ constitutional rights granted to them pursuant
to 42 U.S.C. § 1983 . . . including those under the First, Fourth[,] and
Fourteenth Amendments,” the only specific policy referenced relates to
“detaining and interviewing children without exigent circumstances
(imminent danger of serious bodily harm), court order or consent of their
parent or legal guardian.” The FAC does not indicate that the alleged
First and Fourteenth Amendment violations resulted from municipal
policy or custom.
28             CAPP V. COUNTY OF SAN DIEGO

                      CONCLUSION

    Plaintiffs do not allege plausible § 1983 claims premised
on the Fourth and Fourteenth Amendments, and their Monell
claim is similarly insufficient. Plaintiffs do, however, plead
a plausible First Amendment retaliation claim, and we
conclude that Defendants are not entitled to qualified
immunity on this claim.

     Each party shall bear its own costs on appeal.

  AFFIRMED IN PART and REVERSED AND
REMANDED IN PART.
