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FILED
United States Court of Appeals
Tenth Circuit
PUBLISH
July 27, 2026
UNITED STATES COURT OF APPEALS
Christopher M. Wolpert
FOR THE TENTH CIRCUIT Clerk of Court
KATHERINE TRUJILLO,
Plaintiff - Appellant,
v. No. 25-1201
AMITY PLAZA, LLC; HOUSING
AUTHORITY OF THE CITY OF
LITTLETON, d/b/a South Metro
Housing Options; FRANK
MARTINEZ,
Defendants - Appellees.
Appeal from the United States District Court
for the District of Colorado
(D.C. No. 1:23-CV-01019-CMA-TPO)
Jessica McBryant (Nelson Boyle on the briefs), of Ramos Law LLC, Northglenn, Colorado, for Plaintiff-Appellant.
Shannon M. Hurley (Ryan L. Winter and Jared R. Ellis with her on the brief), of Hall & Evans, LLC, Denver, Colorado, for Defendants-Appellees Amity Plaza, LLC and Housing Authority of the City of Littleton d/b/a South Metro Housing Options.
E. Catlynne Shadakofsky (John Lebsack and Doug Poling with her on the brief), of White & Steele, Denver, Colorado, for Defendant-Appellee Frank Martinez.
Before EID, EBEL, and FEDERICO, Circuit Judges.
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FEDERICO, Circuit Judge.
After Katherine Trujillo was allegedly raped by Frank Martinez, one
of her landlord’s employees, she filed suit against both her landlord and
Martinez. Trujillo sought to hold her landlord vicariously liable because,
she argued, Martinez was aided by his employment in committing the rape.
As such, she sought to invoke the aided-by-agency exception to the usual
test for vicarious liability. But that exception is exceedingly narrow, and
Trujillo has not satisfied its strict requirements. Exercising our jurisdiction
under 28 U.S.C. § 1291, we affirm the judgment entered against Trujillo.
I
A
In January 2021, Trujillo moved into Amity Plaza, LLC, an apartment
owned and operated by the Housing Authority of the City of Littleton
(collectively, Amity Plaza). 1 Two months later, Trujillo encountered
Martinez – a maintenance worker employed by Amity Plaza – for the first
time when he responded to a work order that she had submitted.
1Because this appeal comes to us on summary judgment entered
against Trujillo, we recite the facts in the light most favorable to her as the non-moving party. Garrett v. Hewlett-Packard Co., 305 F.3d 1210, 1213 (10th Cir. 2002).
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From there, things escalated quickly. Martinez acquired Trujillo’s
phone number and began to harass her through repeated calls and texts.
While those calls began with Martinez inquiring about whether Trujillo
could help him acquire a piece of art, they soon veered into uncomfortably
personal territory. Martinez confided in Trujillo about the difficulties he
had regarding his child’s gender expression and sexual identity, as well as
about his estrangement from his wife. He continued to do so even after
Trujillo asked him to stop calling.
Eventually, Martinez’s verbal harassment became physical. On one
occasion, he exposed his penis and forced Trujillo to touch it. On another,
Martinez pulled Trujillo onto a couch and climbed on top of her. In that
instance, when Trujillo told Martinez to stop, he complied and left her
apartment. But on May 3, 2021, Martinez allegedly went further and did
not stop.
That day, Martinez was not supposed to be at Trujillo’s apartment
because she had not requested maintenance, and he was responding to a
work order elsewhere. Yet after Martinez completed that work order, he
went to Trujillo’s apartment. The building was open to the public, so
Martinez was able to enter and make his way to Trujillo’s unit without
using the master key he had been assigned as an Amity Plaza employee.
The door to Trujillo’s unit was also unlocked, so when Martinez arrived, he
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was again able to enter her unit without using his master key. Once he
entered, Martinez pinned Trujillo down and raped her.
B
Trujillo filed suit against both Amity Plaza and Martinez. By the time
her case reached summary judgment, three claims remained: a pair of
federal Fair Housing Act (FHA) claims against Amity Plaza and Martinez,
and a state sexual assault claim against Martinez alone. Amity Plaza (but
not Martinez) moved for summary judgment on the FHA claims.
In deciding the motion, the district court first held that Trujillo had
failed to present evidence establishing Amity Plaza was directly liable for
any FHA violation. It was undisputed that Trujillo did not report Martinez
to Amity Plaza until after the alleged rape, so Amity Plaza was not on notice
that it needed to act until then. 2 By that time, there was no action that
Amity Plaza could have taken with respect to Martinez’s employment since
he had already quit his job. Instead, Amity Plaza responded by offering to
move Trujillo into a different apartment unit, although Trujillo declined
that offer. The district court concluded that, in these circumstances, Amity
Plaza was not directly liable to Trujillo.
2 Before this, Amity Plaza had received a sexual harassment
complaint against Martinez that was unrelated to Trujillo. After investigating, Amity Plaza was unable to substantiate the complaint.
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The district court next held that Amity Plaza was not vicariously
liable for Martinez’s actions. The usual test for vicarious liability turns on
whether an employee acted within the scope of the employment. That is, an
employer is vicariously liable for employee acts within the scope of
employment but not for acts outside of it. Meyer v. Holley, 537 U.S. 280,
285–86 (2003). However, Trujillo did not argue that Martinez was acting
within the scope of his employment when he allegedly raped her. Instead,
she invoked the aided-by-agency exception to the usual test, which would
hold Amity Plaza vicariously liable if Martinez’s employment “aided [him]
in accomplishing” the rape. Burlington Indus., Inc. v. Ellerth, 524 U.S. 742,
759 (1998) (quoting Restatement (Second) of Agency § 219(2)(d)).
The district court determined that the exception did not apply here
because Trujillo had not introduced evidence establishing a “nexus between
[] Martinez’s position as a maintenance worker and the harassment he
perpetrated.” Aplt. App. VI at 57. For these reasons, the district court
granted summary judgment in favor of Amity Plaza on Trujillo’s FHA
claims. Then, even though Martinez did not separately move for summary
judgment, the district court sua sponte granted summary judgment in his
favor on the FHA claims, too. That left just Trujillo’s state sexual assault
claim against Martinez. Having resolved all federal claims and lacking
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diversity jurisdiction over the remaining state claim, the district court
declined supplemental jurisdiction and entered judgment against Trujillo.
In response, Trujillo moved under Federal Rule of Civil Procedure
59(e) for reconsideration of the district court’s sua sponte summary
judgment in favor of Martinez. The district court acknowledged that it had
failed to provide Trujillo the notice required by Rule 56(f) before entering
sua sponte summary judgment, but it denied Trujillo’s motion because it
found that she had suffered no prejudice from its prior ruling. Trujillo
timely appealed.
On appeal, Trujillo presents three issues. Primarily, Trujillo
challenges the district court’s grant of summary judgment to Amity Plaza
on her FHA claims. On that point, Trujillo does not contest the district
court’s holding on direct liability, arguing only that the district court
misapplied the aided-by-agency exception to reject vicarious liability. Next,
she contends that the district court was wrong to sua sponte grant summary
judgment for Martinez. And finally, she asserts that the district court
should not have declined supplemental jurisdiction. We discuss and resolve
each of these issues in turn.
II
We start with vicarious liability. As the parties have presented this
issue on appeal, we must answer only a narrow question. Vicarious liability
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is a form of no-fault liability, so we are not called upon to assess (and do not
assess) Amity Plaza’s blameworthiness or culpability. See Meyer, 537 U.S.
at 282. There is also no dispute that Martinez was acting outside the scope
of his employment – the traditional measure of vicarious liability – when he
allegedly raped Trujillo. So, we take it as a given that Martinez acted upon
his own personal motives when he entered Trujillo’s apartment. The only
question we confront is whether the aided-by-agency exception applies to
hold Amity Plaza strictly liable for Martinez’s actions.
Because this question comes to us on summary judgment, we review
the district court’s decision de novo, employing the same test that applies
in district court. Siloam Springs Hotel, LLC v. Century Sur. Co., 906 F.3d
926, 930 (10th Cir. 2018). Under this standard, “[w]e will affirm a grant of
summary judgment if there is no genuine dispute of material fact and the
prevailing party is entitled to judgment under the law.” Grynberg v. Total
S.A., 538 F.3d 1336, 1346 (10th Cir. 2008); accord Fed. R. Civ. P. 56(a).
As best we can tell, neither the Supreme Court nor any of our sister
circuits have addressed how, or even if, the aided-by-agency exception
applies to FHA claims. We thus begin our analysis by discussing whether
and how the aided-by-agency exception applies to FHA claims. We conclude
that the FHA recognizes the aided-by-agency exception and sketch out a
high-level framework for applying the exception. Then, applying that
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framework, we determine that Trujillo has failed to create a genuine
dispute over any material fact that could trigger vicarious liability under
the exception. 3
A
Although the FHA does not expressly say so, “it is well established
that the [FHA] provides for vicarious liability” because it incorporates the
“traditional” and “ordinary” rules of agency. Meyer, 537 U.S. at 285, 287.
These traditional rules make up a body of law that this court has referred
to as the “general common law of agency.” Alfaro-Huitron v. Cervantes
Agribusiness, 982 F.3d 1242, 1259 n.6 (10th Cir. 2020) (quoting Cmty. for
Creative Non-Violence v. Reid, 490 U.S. 730, 740–41 (1989)). The general
common law is federal, so it takes its shape from the “body of case law
developed over time” by the federal courts as they apply agency principles
to claims arising under federal statutes. Ellerth, 524 U.S. at 754–55. Other
sources like state law and the Restatements can be instructive. Id. at 755;
3 Amity Plaza suggests that Trujillo may have forfeited some of her
arguments on the aided-by-agency exception. To the extent Amity Plaza is correct, we nonetheless exercise our “discretion to consider [those] arguments.” Ave. Cap. Mgmt. II, L.P. v. Schaden, 843 F.3d 876, 886 (10th Cir. 2016).
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see also Alfaro-Huitron, 982 F.3d at 1259 n.6. However, these other sources
are not binding on us. 4 Ellerth, 524 U.S. at 754–55.
The application of general common law means that we do not start
with a clean slate when determining whether the FHA recognizes the aidedby-agency exception. That is because other federal statutes, like Title VII,
also apply the general common law of agency. See id. at 754. And in the
Title VII context, the Supreme Court has previously held that the general
common law recognizes the aided-by-agency exception. Id. at 758 (quoting
Restatement (Second) of Agency § 219(2)(d)); see also Faragher v. City of
Boca Raton, 524 U.S. 775, 802 (1998). Since the same agency principles
apply to both Title VII and the FHA, the aided-by-agency exception also
applies to FHA claims.
Of course, it is one matter to decide that the aided-by-agency
exception is available under the FHA. It is another matter, and a much
more difficult one given the scarce caselaw, to determine how the exception
4 The parties spill much ink arguing over federal housing regulations
on vicarious liability. With one exception addressed later in this opinion, there is no need for us to grapple with or further discuss these regulations. That is because the regulations state only the general principle that traditional agency rules apply in the FHA context. See 24 C.F.R. § 100.7(b); 81 Fed. Reg. 63054, 63072 (Sept. 14, 2016) (adopting “well-established principles of agency law”). The Supreme Court already made that point clear in Meyer, 537 U.S. at 285.
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applies to a given set of facts. We therefore start from the fundamental
premise, drawn from an emerging consensus among the state courts, that
aided-by-agency is a narrow and disfavored exception to the usual rule
limiting vicarious liability to acts within the scope of employment.
At a high level, the aided-by-agency exception triggers vicarious
liability whenever an employee “was aided in accomplishing the tort by the
existence of the [employment] relation.” Ellerth, 524 U.S. at 759 (citation
omitted). But ever since the Supreme Court adopted the exception in
Ellerth, state courts have expressed concern about the exception’s
potentially broad reach. As the Iowa Supreme Court observed, “[a]n
argument can almost always be made at some level of generality that an
employee’s tortious conduct was ‘aided’ by the employee’s job.” Martin v.
Tovar, 991 N.W.2d 760, 768 (Iowa 2023). For that reason, the Alaska and
New Mexico Supreme Courts noted that the doctrine “risks an unjustified
expansion of employer tort liability for acts of employees.” Ayuluk v. Red
Oaks Assisted Living, Inc., 201 P.3d 1183, 1199 (Alaska 2009); Spurlock v.
Townes, 368 P.3d 1213, 1217 (N.M. 2016) (quoting Ayuluk). And the
Vermont Supreme Court expressed concern that a broad view of the doctrine
could “make[] a principal liable for all intentional torts of an agent in all
circumstances.” Doe v. Forrest, 853 A.2d 48, 60 (Vt. 2004).
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Some states have responded to these concerns by rejecting the aidedby-agency exception. The Michigan Supreme Court declined to adopt the
exception altogether out of a “recogni[tion] that were [it] to adopt the
exception [it] would potentially be subjecting employers to strict liability.”
Zsigo v. Hurley Med. Ctr., 716 N.W.2d 220, 226 (Mich. 2006). And the Iowa
Supreme Court cabined the exception to hostile work environment claims
alone. Martin, 991 N.W.2d at 766, 768. The American Law Institute, too,
has now rejected the exception after initially endorsing it in the
Restatement (Second) of Agency. See Restatement (Third) of Agency § 7.08
cmt. b (“This Restatement does not include ‘aided in accomplishing’ as a
distinct basis for an employer’s . . . vicarious liability.”). 5
Unlike the state courts canvassed above, we do not have the option of
rejecting the aided-by-agency exception because the Supreme Court has
incorporated the exception into federal law via the general common law of
agency. It is for the Supreme Court, not us, to decide whether to eliminate
5 In addition to deleting the aided-by-agency exception in the Third
Restatement, the American Law Institute also appended a note to § 219 of the Second Restatement. The note indicates that the exception “was not approved by [Institute] membership and thus did not represent the position of the [Institute].” Restatement (Second) of Agency § 219. It is not completely clear that this note is accurate. See generally Danielle Dascher, “Restating” the Record: Evaluating ALI’s Aided-by-Agency Disclaimer, 117 Law Libr. J. 108 (2025). Regardless, what is clear is that the Institute has now repudiated the aided-by-agency exception.
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the aided-by-agency exception in response to criticisms and concerns about
the doctrine. See Rodriguez de Quijas v. Shearson/Am. Exp., Inc., 490 U.S.
477, 484 (1989). But our survey of the authorities above illustrates the
growing trend towards applying the aided-by-agency exception narrowly
and cautiously.
To that end, we recognize that the bar for triggering the exception is
high. Indeed, the Supreme Court acknowledged the need for strict limits
even as it adopted the aided-by-agency exception. See Ellerth, 524 U.S. at
760. For one, the Supreme Court “require[d] the existence of something
more than the employment relation itself” to trigger the exception. Id. And
it held the mere fact that employment created “[p]roximity and regular
contact,” or created “a captive pool of potential victims,” was not enough.
Id. So, at least in the Title VII context, the exception usually creates
vicarious liability only when supervisors exercise their supervisory
authority over an employee. Id. at 760–63.
While the concept of supervisory authority over a subordinate
employee does not translate neatly into the housing context under the FHA,
the more general principle – that the exercise of authority is crucial to
triggering the exception – does translate. Many of the state courts that have
adopted the exception have emphasized the importance of authority to the
aided-by-agency analysis. As an example, when the Delaware Supreme
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Court applied the exception to police departments, it did so in large part
because police officers hold “potent coercive power” over members of the
community. Sherman v. State Dep’t of Pub. Safety, 190 A.3d 148, 181 (Del.
2018). The Vermont Supreme Court likewise applied the exception to law
enforcement agencies due to the “extraordinary power that a law
enforcement officer has over a citizen.” Forrest, 853 A.2d at 61. And
tellingly, it declined to extend the exception to hold churches liable for the
actions of their pastors because it concluded that pastors did not possess
similarly extraordinary power. Doe v. Newbury Bible Church, 933 A.2d 196,
198–99 (Vt. 2007).
Other states have expressly made the presence of authority an
element of the aided-by-agency exception. In Alaska, the exception applies
only in “cases where an employee has by reason of his employment
substantial power or authority to control important elements of a
vulnerable tort victim’s life or livelihood.” Ayuluk, 201 P.3d at 1199. And
New Mexico has the same rule. Spurlock, 368 P.3d at 1217 (quoting Ayuluk).
All that said, authority is not the be-all-end-all of the doctrine. The
aided-by-agency exception can also apply when an employee takes
advantage of “some special mechanism afforded to him by his employment”
when committing a tort. Yucis v. Sears Outlet Stores, LLC, 813 F. App’x 780,
786 (3d Cir. 2020). For instance, the exception applies “where a telegraph
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operator sends false messages” or where “the manager of a store . . . is
enabled to cheat the customers because of his position.” Restatement
(Second) of Agency § 219 cmt. e. 6 The telegraph operator and store manager
do not have any meaningful authority over the victims in those examples,
but their employment gives them special privileges or access that enable
their torts.
Other circuits have invoked this special privilege rule to trigger the
aided-by-agency exception. For instance, the First Circuit applied the
exception when a hotel manager used his master key to enter the plaintiff’s
room and rape her. Costos v. Coconut Island Corp., 137 F.3d 46, 50 (1st Cir.
1998). And the Eighth Circuit applied the exception when a police chief
“used a government-issued computer and official credentials to obtain [a
plaintiff]’s private information.” Orduno v. Pietrzak, 932 F.3d 710, 732 (8th
Cir. 2019).
The key to this special privilege rule is that the privilege or access
must be “unique” and not available to the public writ large. Iverson v. NPC
Int’l, Inc., 801 N.W.2d 275, 279 (S.D. 2011). Or put differently, to trigger
6 The Supreme Court adopted the Second Restatement’s formulation
of the aided-by-agency exception. Ellerth, 524 U.S. at 758–59. Therefore, we cite to it as persuasive authority even though, as explained above, the American Law Institute has since abandoned the exception. See
Restatement (Third) of Agency § 7.08 cmt. b.
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the aided-by-agency exception, it must be that the employee “could not have
[committed a tort] but for his official position” and the attendant special
privilege. Orduno, 932 F.3d at 718. In Costos, for instance, the hotel
manager’s master key was unique to his position and not available to the
typical member of the public. And in Orduno, the average citizen would not
be able to acquire the log-in credentials that the police chief used.
One final note. The exception applies only when an employee is “aided
in accomplishing the tort by” his employment. Restatement (Second) of
Agency § 219(2)(d) (emphasis added). This means the mere presence of some
sort of authority or special privilege is not enough on its own to trigger the
exception. The employee needs to actually use and be aided by that
authority or privilege when committing a tort. In other words, there must
be some causal nexus between the authority or privilege and the tort.
***
To summarize, the general common law of agency establishes that the
aided-by-agency exception applies in two situations. First, the exception can
apply when an employee exercises significant authority over a tort victim
by virtue of his employment. Second, the exception can apply when an
employee gains a special privilege or access that is not available to the
general public. In both circumstances, the employee must use the authority
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or privilege to commit the tort. Otherwise, the employment did not “aid” the
commission of the tort.
We acknowledge that these principles may not flesh out a complete
framework for the aided-by-agency exception, and difficult line drawing
questions likely remain to be answered. How great must an employee’s
authority be, and how strong must the causal nexus be, to trigger the
exception? We do not attempt to draw all those lines here in this appeal. As
we explain shortly, wherever the lines may be, Trujillo’s claims still fail to
satisfy the aided-by-agency exception.
B
Having established a framework for the aided-by-agency exception,
we now proceed to apply that framework to Trujillo’s claims.
The record does not indicate that Martinez had any meaningful
authority over Trujillo. As a maintenance worker, Martinez did not control
Trujillo’s lease or rent. Nor does the record suggest that Martinez could
have coerced Trujillo by withholding maintenance services. Although
Martinez could have personally refused to respond to Trujillo’s work orders,
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Amity Plaza employed other maintenance workers that it could have
dispatched to handle Trujillo’s requests. 7
However, Martinez did possess a special privilege and access not
available to the public at large: a master key. The problem for Trujillo’s
claims is that there is no evidence Martinez used that master key the day
he allegedly raped Trujillo. As Trujillo’s counsel conceded at oral argument,
the building that Trujillo lived in was open to the public, so Martinez did
not need any special access to enter the building. And as Trujillo herself
testified, her door was unlocked when Martinez entered, so Martinez did
not use his master key there, either. Given that Martinez never used his
master key, there is no causal nexus between the special privilege of his
employment and his alleged rape of Trujillo; the master key did not “aid”
Martinez in committing the rape.
Trujillo points to two other facts that she claims can trigger the aidedby-agency exception. First, she notes that Martinez used a work phone to
7 Pointing to federal housing regulations, Trujillo argues “a housing
provider’s agent” necessarily “holds a position of power and authority over the victimized resident . . . , regardless of the agent’s specific duties.” Op. Br. at 39 (quoting 81 Fed. Reg. at 63072). However, the quoted regulation specifically addresses agents who, unlike Martinez, have “power and control over the terms or conditions of the housing environment.” 81 Fed. Reg. at 63072. The regulation also recognizes that “[a]gency law must be applied to the specific facts at issue.” Id. So, regardless of whether the regulation receives any level of deference, it does not compel a different result here.
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call and text her. But a work phone is not a special privilege of Martinez’s
employment because anyone can get a phone. Regardless, the fact that
Martinez was able to call and text with his work phone shows only that the
work phone helped facilitate “[p]roximity and regular contact” with Trujillo,
which is not enough to trigger the exception. Ellerth, 524 U.S. at 760.
Second, Trujillo observes that Martinez was wearing his work uniform
the day of the alleged rape. However, nothing in the record indicates that
the uniform played any role in the rape. It did not appear to facilitate
Martinez’s entry into Trujillo’s building, nor did it appear to lower Trujillo’s
guard.
Ultimately, the record does not indicate that Martinez possessed any
authority over Trujillo, nor that any special privilege of his employment
aided him in committing the alleged rape. Trujillo has therefore failed to
create any genuine disputes of material fact regarding the aided-by-agency
exception, and we affirm the summary judgment in favor of Amity Plaza.
III
With that, we turn to the district court’s sua sponte grant of summary
judgment on the FHA claims in favor of Martinez. Since Trujillo raised this
issue to the district court as a Rule 59(e) motion to alter or amend the
judgment, we review for abuse of discretion. Headwaters Res., Inc. v. Ill.
Union Ins. Co., 770 F.3d 885, 899 (10th Cir. 2014). As such, we will not
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disturb the district court’s Rule 59(e) ruling unless we have “a definite and
firm conviction that the [district] court made a clear error of judgment or
exceeded the bounds of permissible choice.” Id. (citation omitted).
Rule 56(f) supplies the substantive standards for assessing sua sponte
grants of summary judgment. Under that rule, a district court must “giv[e]
notice and a reasonable time to respond” before acting on a sua sponte basis.
Fed. R. Civ. P. 56(f). But not every failure of notice requires the district
court to revisit its judgment. “[I]f the losing party suffered no prejudice from
the lack of notice,” there is no reason to amend the judgment. A.M. v.
Holmes, 830 F.3d 1123, 1137 (10th Cir. 2016) (quoting Johnson v. Weld
County, 594 F.3d 1202, 1214 (10th Cir. 2010)). In this appeal, Trujillo did
not attempt to develop any prejudice argument until her reply brief. She
has therefore waived such argument, and we can affirm on that basis alone.
See In re Motor Fuel Temperature Sales Pracs. Litig., 872 F.3d 1094, 1112
& n.5 (10th Cir. 2017).
The only argument that Trujillo properly advances is that we should
reverse the grant of summary judgment to Martinez “for the same reasons
that the district court erred in granting summary judgment” to Amity
Plaza. Op. Br. at 54. However, we now hold that the district court did not
err in granting summary judgment to Amity Plaza. Accordingly, we also
affirm summary judgment as to Martinez.
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IV
Finally, we address supplemental jurisdiction. When a district court
“has dismissed all claims over which it has original jurisdiction,” it may and
usually should decline supplemental jurisdiction over the remaining state
claims. Koch v. City of Del City, 660 F.3d 1228, 1248 (10th Cir. 2011)
(quoting 28 U.S.C. § 1367(c)(3)). We review decisions to decline
supplemental jurisdiction in such circumstances for abuse of discretion. Id.
Trujillo contends that the district court should have maintained
supplemental jurisdiction over her state sexual assault claim against
Martinez. But once again, Trujillo’s only argument for maintaining
jurisdiction is that the district court should not have granted summary
judgment on her federal FHA claims. That argument fails because we affirm
the district court’s grant of summary judgment. We thus conclude that the
district court did not abuse its discretion when declining supplemental
jurisdiction.
AFFIRMED. 8
8 At the end of her opening brief, Trujillo asks for fees and costs under
42 U.S.C. § 3613, Federal Rule of Appellate Procedure 39, and Tenth Circuit Rule 39. Assuming for argument’s sake that she properly raised her request and that fees and costs are available, we deny her request because she has not prevailed on appeal.
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