 United States Court of Appeals
          FOR THE DISTRICT OF COLUMBIA CIRCUIT



Argued October 6, 2017                  Decided April 13, 2018

                         No. 15-7023

  BRIDZETTE LANE, INDIVIDUALLY AND AS THE PERSONAL
  REPRESENTATIVE OF THE ESTATE OF RALPHAEL BRISCOE,
                     APPELLANT

                               v.

 DISTRICT OF COLUMBIA, A MUNICIPAL CORPORATION AND
 CHAD LEO, DISTRICT OF COLUMBIA METROPOLITAN POLICE
                 DEPARTMENT OFFICER,
                      APPELLEES


         Appeal from the United States District Court
                 for the District of Columbia
                     (No. 1:12-cv-00514)


    Billy Ponds argued the cause and filed the brief for
appellant.

    Carl J. Schifferle, Assistant Attorney General, Office of the
Attorney General for the District of Columbia, argued the cause
for appellees. With him on the brief were Karl A. Racine,
Attorney General, Todd S. Kim, Solicitor General, and Loren L.
AliKhan, Deputy Solicitor General.

   Before: SRINIVASAN and WILKINS, Circuit Judges, and
SENTELLE, Senior Circuit Judge.
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   Opinion for the Court filed by Senior Circuit Judge
SENTELLE.

     SENTELLE, Senior Circuit Judge: Appellant Bridzette Lane
brought this action on her own behalf and as the personal
representative of the estate of her deceased son Ralphael Briscoe
for wrongful death and survivorship against the District of
Columbia and three Metropolitan Police Department officers.
Of the twenty counts alleged in the amended complaint, several
counts were voluntarily dismissed, summary judgment was
entered in favor of the defense as to some counts, and some
counts went to trial, ending in a jury verdict for the remaining
defendants, the District of Columbia and Officer Chad Leo.
Lane appeals from the judgments in favor of the District and
Officer Leo. For the reasons set forth below, we affirm the
judgment of the district court.

                      I. BACKGROUND

     The events giving rise to this action occurred in April 2011,
when appellee Leo and three other officers were on patrol as
part of the Gun Recovery Unit of the Metropolitan Police
Department (“MPD”). The officers encountered Briscoe in an
apartment parking lot. When one of the officers asked Briscoe
if he was carrying a gun, Briscoe fled. Two of the officers
pursued Briscoe on foot, while Leo and another officer pursued
in a police vehicle. A portion of the chase was captured on a
Police Department video camera.

     While there is some conflict in the evidence, we relate the
further events in the light most favorable to the defendant-
appellees as we must in reviewing a jury verdict. See Pitt v.
Dist. of Columbia, 491 F.3d 494, 502 (D.C. Cir. 2007). Leo
testified that he saw Briscoe’s right hand moving toward his
waistband, causing Leo to fear that he was reaching for a gun.
                                3

Briscoe repeatedly looked over his left shoulder, toward the
pursuing officers, and turned toward the police vehicle, pointing
what appeared to Leo to be a gun. Leo fired two shots. One
struck Briscoe in the back and one in the buttocks. Briscoe was
transported to the hospital where he died as a result of the
wounds.

     A police search of the scene of the shooting recovered no
actual firearm, but it did produce a broken BB gun, which
closely resembled an actual firearm, specifically a Walther PPK
pistol. No fingerprints were found on the weapon. Police
technicians swabbed the BB gun for DNA, but there is no
evidence that the swabs were ever tested.

     Lane brought the present action against the District of
Columbia and MPD Officers Chad Leo, Jeremy Sharpton, and
Guillermo Rivera on behalf of herself and Briscoe’s estate.
Lane’s complaint alleged twenty counts for: violations of the
Fourth, Fifth, and Fourteenth Amendments, including municipal
liability for the failure to train, supervise, and negligent hiring
under 42 U.S.C. § 1983; assault; battery; false arrest; negligent
infliction of emotional distress; common law negligence in
hiring, training, supervision, and retention; common law
negligence; and survival and wrongful death under the D.C.
Code. The defendants moved to dismiss Lane’s amended
complaint. The district court granted in part and denied in part
the motion to dismiss, dismissing Lane’s Fourteenth
Amendment claim. Additionally, Lane agreed to dismiss her
claims against Rivera and Sharpton without prejudice.

    The remaining defendants, the District and Officer Leo,
moved for summary judgment. In her response to the summary
judgment motion, Lane voluntarily dismissed nine of her claims.
The district court granted in part the District’s motion for
summary judgment and dismissed Lane’s claims against the
                                 4

District for municipal liability under § 1983, for common law
negligence in hiring, training, supervision, and retention, and for
violation of due process under the Fifth Amendment. Lane v.
Dist. of Columbia, 72 F. Supp. 3d 215, 219 (D.D.C. 2014). The
case proceeded to trial on the remaining causes of action against
Officer Leo for excessive force in violation of the Fourth
Amendment and against the District and Officer Leo for false
arrest, assault, battery, negligent infliction of emotional distress,
and common law negligence.

     Ten days before the start of the trial, Lane learned that a
fingerprint report from the BB gun was not turned over during
discovery. The district court permitted Lane to depose David
Murray, an officer knowledgeable about the results of the search
and the report. During the deposition, Lane learned that DNA
swabs were taken from the BB gun, which also had not been
disclosed during discovery. Following this revelation, Lane
filed a motion for sanctions based on these late disclosures
seeking a default judgment or a five-day continuance, leave to
amend the witness list to include Officer Murray, time to allow
additional depositions on fingerprinting and biological testing,
permission to name experts on this subject, a bar on the
defendants eliciting testimony from Officer Murray or other
witnesses about this subject matter, an instruction to the jury on
the substantial delay caused, and attorney’s fees. The district
court verbally admonished the defendants, but did not grant
Lane’s motion for sanctions.

     Before trial, the defendants moved in limine to exclude
some items of evidence that the plaintiff anticipated offering,
two of which are relevant for this appeal. First, they moved to
exclude Briscoe’s cell phone bill covering the time of the
shooting incident. Second, they sought to exclude Lane’s
anticipated testimony that Briscoe suffered from ADHD and
bipolar disorder. As to the phone bill, the court granted the
                               5

motion but accepted a stipulation from the defendants that
Briscoe was on the phone when the officers encountered him.
As to the evidence concerning Briscoe’s alleged mental
conditions, the court excluded the evidence except insofar as it
might be relevant to Briscoe’s earning capacity should the jury
reach the issue of damages.

     The case proceeded to trial. During the trial, Lane
voluntarily dismissed her claim for negligent infliction of
emotional distress. Following the six-day trial and two days of
deliberations, the jury returned a verdict in favor of the
defendants on the remaining counts. In answer to a special
interrogatory, the jury found that Briscoe “had an object in his
hand that reasonably looked like a real gun to Defendant Leo at
the time” of the shooting. Following trial, Lane moved for a
new trial, arguing that the jury’s verdict was against the weight
of the evidence. The district court denied Lane’s motion. Lane
v. D.C., 104 F. Supp. 3d 7-8 (D.D.C. 2015). Lane timely filed
this appeal.

                        II. ANALYSIS

     Lane contends on appeal that the district court erred in
excluding the cell phone bill and the testimony regarding
Briscoe’s alleged mental condition; denying Lane’s motion for
sanctions; and denying Lane’s motion for a new trial. She
further contends that the court erred in the grant of summary
judgment in favor of the District on her failure-to-train and
negligent training claims. For the reasons set forth below, we
reject each of her contentions.
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    A. Trial Proceedings

         1. Exclusion of Evidence

    We review the district court’s grant of the motion in limine
excluding the phone bill and the mental condition evidence for
abuse of discretion. Huthnance v. Dist. of Columbia, 722 F.3d
371, 377 (D.C. Cir. 2013). We will reverse an erroneous
evidentiary ruling only if it affects a party’s substantial rights.
Id. Neither of the exclusions in this case is reversible error.

              a. Cell Phone Bill

     The cell phone bill shows the phone in use between 2:22 pm
and 2:25 pm at the time of the shooting, which other evidence
established at 2:24:24 pm. Because the defense stipulated that
Briscoe was on the phone when they encountered him, and there
was no apparent relevance to the question of whether Briscoe
affirmatively terminated his phone call within the next three
minutes, we cannot say that the district court abused its
discretion by excluding the cell phone bill as cumulative. Even
if a call remained connected at the time Briscoe was shot, that
evidence would have minimal relevance and its exclusion thus
would not affect Briscoe’s substantial rights, see Muldrow ex
rel. Estate of Muldrow v. Re-Direct, Inc., 493 F.3d 160, 168
(D.C. Cir. 2007), given that Briscoe may very well have put his
phone away without hanging up when he began running.

     Lane argues that the cell phone evidence became probative
because two of the police witnesses, including appellee Leo,
testified that they did not recall Briscoe talking on the phone.
Nonetheless, in light of the defense stipulation, the evidence
remains cumulative. Furthermore, even if we credit Lane’s
argument that the bill became relevant because of the testimony
of two witnesses that they did not recall the circumstance to
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which the defense had stipulated, “when the court’s initial
[evidentiary] ruling, correct when made, is proved erroneous in
the light of subsequent evidence,” the objecting party must
renew the objection. United States v. Sheehan, 512 F.3d 621,
627 (D.C. Cir. 2008) (quoting United States v. Lewis, 433 F.2d
1146, 1152 (D.C. Cir.1970)). Because Lane did not seek to
introduce the cell phone bill or renew her objection during the
trial, we will not reverse the district court’s decision to exclude
the cell phone bill.

              b. Lane’s Testimony on Briscoe’s ADHD and
              Bipolar Disorder

     Lane next argues that the district court erred in excluding
her testimony that Briscoe suffered from ADHD and bipolar
disorder. While this testimony would have been of questionable
relevance at best, the trial court clearly did not err in excluding
Lane’s testimony on Briscoe’s medical condition. A trial court
does not err by excluding evidence of a medical condition from
a lay witness. A lay witness may not testify based on scientific
or other specialized knowledge. Fed. R. Evid. 701(c). We do
“not disturb the ruling of a district court where . . . an
independent basis for that ruling is uncontested.” Meijer, Inc. v.
Biovail Corp., 533 F.3d 857, 863 (D.C. Cir. 2008). Even if the
evidence would have been probative, Lane cannot credibly
contend that she was qualified to testify about a medical
diagnosis. The district court did not abuse its discretion in
excluding Lane’s testimony on Briscoe’s medical condition.

         2. Sanctions

     Next, Lane argues that the district court erred by not
awarding sanctions against the defendants for discovery
violations. Lane argues that two discovery violations—the late
disclosures of a fingerprint report and the existence of a DNA
                                8

swab of the BB gun—prejudiced her case, and therefore the
district court should have sanctioned the defendants. “[T]he
district court has broad discretion to impose sanctions for
discovery violations.” Bonds v. Dist. of Columbia, 93 F.3d 801,
807 (D.C. Cir. 1996). “When reviewing the district court’s
denial of sanctions, the question is not whether we would have
ordered sanctions, but instead is whether the district court
abused its discretion in declining to do so.” Giles v. Transit
Emps. Fed. Credit Union, 794 F.3d 1, 15 (D.C. Cir. 2015).

     Lane argues that the late disclosure of the fingerprint report
prejudiced her because it was too late for her to engage a
fingerprint expert. Lane contends that her expert could
testify—consistent with her theory that the BB gun was
planted—that the fingerprint testing was flawed and that if a
different testing method was used it might have picked up
fingerprints belonging to someone other than Briscoe. The
district court found that such testimony would require a “chain
of inferences” that was “too attenuated” and would confuse the
jury. Lane also argues that a fingerprint expert could testify that
if Briscoe handled the BB gun, he would have left fingerprints.
However, the defendants timely disclosed that no fingerprints
were found on the BB gun. It was only the report itself that was
disclosed late. Because Lane knew there were no fingerprints,
she had the opportunity to pursue this type of expert testimony
despite the late disclosure of the fingerprint report.

    Next, Lane argues that the late disclosure of the DNA swab
prejudiced her because it was too late for her to depose other
witnesses about whether the swab was tested for DNA. The
defendants offered affidavits that the swab was never tested for
DNA and the district court concluded that Lane had “no basis”
to conclude the swab was tested. Therefore, any additional
questioning by Lane regarding whether the swab was tested was
                                9

unlikely to lead to any probative evidence, and we cannot hold
that the district court abused its discretion in so ruling.

     Further, there is no evidence or accusation that the
defendants’ discovery omissions were intentional. Given the
district court’s broad discretion regarding sanctions, Lane’s
failure to show prejudice from the discovery violations, and the
lack of intentional misconduct, we find no error in the district
court’s denial of Lane’s motion for sanctions.

         3. Motion for a New Trial

     Lane also appeals the district court’s denial of her motion
for a new trial, arguing that the jury verdict was against the
weight of evidence. Our review of a district court’s denial of
such a motion is extremely limited. Daskalea v. Dist. of
Columbia, 227 F.3d 433, 443 (D.C. Cir. 2000). The district
court’s consideration of such a motion and our consideration of
the district court’s denial begins with the proposition that a jury
verdict stands “unless the evidence and all reasonable inferences
that can be drawn therefrom are so one-sided that reasonable
men and women could not disagree on the verdict.” Czekalski
v. LaHood, 589 F.3d 449, 456 (D.C. Cir. 2009) (internal
quotation marks omitted). In urging that we should nonetheless
reverse the district court’s denial of the motion, appellant relies
heavily on a single piece of evidence—the police camera video.

     Lane argues that the video evidence clearly shows that
Briscoe was not carrying a gun. Therefore, Lane reasons, a jury
verdict resting on the conclusion that Officer Leo reasonably
believed that he saw a gun was against the weight of the
evidence. Lane supports her contention by arguing that Officer
Leo reviewed the video frame-by-frame during trial and testified
that he did not see anything in Briscoe’s hands. Further, Lane
argues that no evidence was presented at trial that Lane was
                                10

carrying or possessed a BB gun except for Officer Sheehan’s
testimony that Briscoe said “it wasn’t even real” after he was
shot. Advancing her theory that the BB gun was planted, Lane
argues that Officers Katz, Leo, Torres, and Sheehan impeached
themselves by saying no items were moved or touched at the
crime scene.

     In denying the motion for a new trial, the court noted the
following additional evidence was presented to the jury: Officers
Leo and Torres testified that they saw Briscoe holding a gun, the
BB gun recovered from the scene, and the video. The jury was
shown the video and was able to make their own determination
regarding the credibility of the officers’ testimony and whether
Briscoe appeared to have in his hand a cell phone, a shadow, or
a gun. The district court did not abuse its discretion in denying
Lane’s motion for a new trial and we affirm.

    B. Summary Judgment

     Finally, Lane appeals the district court’s partial grant of
summary judgment and the dismissal of her failure-to-train and
negligent training claims against the District. Summary
judgment is appropriate when the moving party demonstrates
that “there is no genuine dispute as to any material fact and the
movant is entitled to judgment as a matter of law.” Fed. R. Civ.
P. 56(a). In determining whether a genuine issue of material
fact exists, the court must view all facts, and draw all reasonable
inferences, in the light most favorable to the party opposing the
motion. Matsushita Elec. Indus. Co. v. Zenith Radio, 475 U.S.
574, 587 (1986). We review de novo the district court’s grant
of summary judgment. Ark Initiative v. Tidwell, 749 F.3d 1071,
1074 (D.C. Cir. 2014).

   A municipality is liable under § 1983 only when the
municipality itself causes the constitutional violation at issue.
                                 11

City of Canton v. Harris, 489 U.S. 378, 385 (1989); see also
Monell v. Dep’t of Soc. Servs. of City of N.Y., 436 U.S. 658
(1978). Policy omissions, including failure to train, which rise
to the level of deliberate indifference, establish a cause of action.
Daskalea, 227 F.3d at 441. There is deliberate indifference
when the need for training reaches a level of moral certainty and
the constitutional consequences become obvious. Id. at 441-42.

     In addition to a failure-to-train cause of action under
Monell, Lane also brought a common law claim for negligent
training. Liability for common law negligent training is
derivative of the employer’s tort liability. “In a negligence case,
the plaintiff has the burden of establishing ‘the applicable
standard of care, a deviation from that standard by the
defendant, and a causal relationship between the deviation and
the plaintiff’s injury.’” Young v. Dist. of Columbia, 752 A.2d
138, 145 (D.C. 2000) (quoting Dist. of Columbia v. Hampton,
666 A.2d 30, 35 (D.C. 1995)).

     Lane offered evidence that there is a national standard of
care in training Gun Recovery Unit (“GRU”) officers and that
the MPD deviated from this standard of care by not providing
the GRU officers specialty training in identifying firearms. If
the GRU officers had specialty training, Lane argues, they
would not have misidentified Briscoe’s cell phone as a gun.

     However, any error that Lane argues may have been
committed by the district court is harmless because the jury
verdict vitiates both the failure-to-train and negligent training
claims. Under a Monell failure-to-train theory, Lane must prove
“a direct causal link” between the failure to train and a
constitutional violation. Harris, 489 U.S. at 385. The initial
inquiry is whether there was a “predicate constitutional
violation.” Baker v. Dist. of Columbia, 326 F.3d 1302, 1306
(D.C. Cir. 2003). The Supreme Court has reasoned, in the
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context of civil rights claims against a municipality, if “[an
officer] inflicted no constitutional injury . . . , it is inconceivable
that [the city] could be liable.” City of Los Angeles v. Heller,
475 U.S. 796, 799 (1986). In this case, the jury found that Lane
did not show that Officer Leo caused any constitutional injury
to Briscoe. Without a predicate constitutional violation, Lane
cannot sustain a failure to train cause of action.

     This also means that Lane’s negligent training claim fails.
Liability for negligent training requires the plaintiff to show a
relationship between a deviation in the standard of care and an
injury. Young, 752 A.2d at 145. Because the jury found no
underlying common law tort, Lane cannot take the next step
required to show a relationship between any deviation from the
standard of care and the injury.

                        III. CONCLUSION

     For the reasons set forth above, we deny Lane’s appeal and
affirm the district court’s judgment.
