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DISTRICT OF COLUMBIA COURT OF APPEALS

Nos. 17-CF-685 & 17-CF-800

TERREZ A. CROCKER & ANDRE R. WALKER, APPELLANTS,

V.

UNITED STATES, APPELLEE.

Appeals from the Superior Court

of the District of Columbia

(CF3-11893-15 & CF3-11894-15)

(Hon. Ronna L. Beck, Trial Judge)

(Argued February 11, 2020 Decided July 1, 2021) 

April E. Fearnley for appellant Terrez A. Crocker. 

James Whitehead, Public Defender Service, with whom Samia Fam and Alice 

Wang, Public Defender Service, were on the brief, for appellant Andre R. Walker.

Eric Hansford, Assistant United States Attorney, with whom Jessie K. Liu, 

United States Attorney at the time the brief was filed, and Elizabeth Trosman, 

Elizabeth H. Danello, Laura Crane, and Alicia M. Long, Assistant United States 

Attorneys, were on the brief, for appellee United States.

Before GLICKMAN, EASTERLY, and MCLEESE, Associate Judges.

GLICKMAN, Associate Judge: Appellants Terrez Crocker and Andre Walker

appeal convictions for robbery and other offenses. Mr. Walker contends the trial 
2

court abused its discretion by denying his request for a missing evidence instruction 

as a sanction for the government’s failure to preserve evidence material to his 

defense. Mr. Crocker joins in that claim. In addition, Mr. Crocker contends the trial 

court impermissibly curtailed bias cross-examination of a key government witness, 

and plainly erred by allowing the prosecutor to vouch for the credibility of witnesses 

in closing argument.

1

 Concluding that appellants’ claims do not entitle them to 

relief, we affirm their convictions.

I.

On the night of August 5, 2015, Thomas Hall left his unlocked white 

Volkswagen Jetta outside his home in Lothian, Maryland, with the keys still in the 

ignition. The car was gone the next morning, and Mr. Hall reported it stolen.

 1

 In his brief on appeal, Mr. Crocker also claimed the trial court erred by 

denying his motion to suppress data collected by a global positioning system (GPS) 

ankle monitor he had worn as a condition of his probation in a previous case. Mr. 

Crocker argued that the police violated his Fourth Amendment rights by obtaining 

the data from CSOSA, the agency supervising Mr. Crocker’s probation, without a 

search warrant. Subsequently, however, we held in United States v. Jackson, 214 

A.3d 464 (D.C. 2019), that “CSOSA did not violate [a probationer’s] reasonable 

expectation of privacy by granting the police access to his GPS tracking data in 

furtherance of their mutual law enforcement objectives” without a search warrant. 

Id. at 486. That holding concededly disposes of Mr. Crocker’s Fourth Amendment 

claim.
3

A few weeks later, between 6:00 p.m. and 7:20 p.m. on the evening of August 

30, the Jetta was involved in three purse snatchings near the Capital Heights Metro 

Station in Washington, D.C. In each instance, two women reportedly emerged from 

the back of the Jetta, grabbed for the victim’s purse, and returned to the car, which 

then drove away. In the last encounter in the series, the victim fended off the women,

called the police at 7:24 p.m., and provided a partial license plate number to the 

dispatcher. By 7:47 p.m., the police located the Jetta. It took off, and the police 

pursued it in a high-speed chase until it crashed. The Jetta’s four occupants — Mr. 

Crocker, the driver; Mr. Walker, the front-seat passenger; and Jessica Robinson and 

fifteen-year-old A.B., the two backseat passengers — were apprehended as they 

attempted to flee on foot. The resulting criminal charges against the group included

conspiracy to commit robbery, robbery, assault with intent to commit robbery, and 

fleeing the police. Mr. Crocker was charged, in addition, with unauthorized use of 

a vehicle during a crime of violence, receiving stolen property, destruction of 

property, and reckless driving.

Ms. Robinson and A.B. entered guilty pleas and were prosecution witnesses 

at appellants’ trial.

2

 Ms. Robinson testified that she and Mr. Walker, who was her 

 2

 Ms. Robinson testified pursuant to a plea agreement with the United States. 

A.B., who had pleaded guilty to the robberies in juvenile court and been committed 
4

boyfriend, met up with Mr. Crocker on the morning of August 30, 2015, at a Dollar 

Plus store, where Mr. Crocker tried unsuccessfully to sell an iPad with a cracked 

screen. Ms. Robinson had met Mr. Crocker on prior occasions and knew him to be 

Mr. Walker’s friend from childhood. After purchasing some cigars and rolling 

papers for marijuana, Ms. Robinson and Mr. Walker got into the car Mr. Crocker 

was driving. Mr. Walker sat in the front passenger seat and Ms. Robinson sat in the 

back seat. In the car, she testified, they smoked marijuana. The two men discussed

a plan to meet and rob a particular “guy” in the area, but they were unable to reach 

this man on the phone to arrange a meeting.3

 

Mr. Crocker then called A.B., whom he referred to as his girlfriend, and drove 

to her apartment to pick her up. A.B. got into the backseat with Ms. Robinson. A.B.

testified she had never met Mr. Walker or Ms. Robinson before that day and did not 

know their names. She referred to the front-seat passenger at trial as “50,” which 

Ms. Robinson testified was one of Mr. Walker’s nicknames. 

 

to the custody of the D.C. Department of Youth Rehabilitation Services (DYRS) at 

a secure residential center called New Beginnings, testified pursuant to a subpoena

without any agreement to cooperate.

3

 For this abortive effort, the grand jury charged appellants with attempted 

robbery. The court acquitted them of that charge at trial.
5

A.B. and Ms. Robinson testified that the group then drove around together the 

rest of the afternoon, smoking marijuana and looking for people to rob. The two 

men pointed out possible targets and encouraged the women to get out and rob them

of their purses. A.B. and Ms. Robinson described three stops in which one or both 

of them committed or attempted to commit a purse snatching at appellants’ 

instigation.

4

The victims of those three purse snatchings also testified at trial. Each 

testified that two women exited a white car, accosted her, robbed or attempted to rob

her, and then retreated to the car, which immediately drove away. In the first 

encounter, which occurred at approximately 6:00 p.m., one of the robbers pushed 

the victim, Ms. R., while the second took her purse, which contained a black Gucci 

wallet. Ms. R. was unable to identify either perpetrator or the people who remained 

in the Jetta during the robbery, but she noticed that the front-seat passenger wore a 

baseball cap. 

 4

 Their accounts differed in various details. Ms. Robinson and A.B. did not 

always agree as to who did what, and A.B. denied actively participating in the second 

purse snatching.
6

In the second incident, the victim, Ms. C., identified Ms. Robinson as the 

robber who grabbed both her purse and an orange cell phone that fell out of the purse 

during the snatching.

5

 Ms. C. testified that she saw two men in the front seat of the 

white car and heard them yelling for the women to hurry up. She identified the car 

as a Volkswagen. She could not identify the two men inside it.

The third victim, Ms. E., identified Ms. Robinson and A.B. as the two women 

who ran up behind her and tried to take her purse away from her. Ms. E. fought 

them off and the two women ran back into a white Volkswagen Jetta that was idling 

nearby. Ms. E. could not identify the individuals waiting in the car. The Jetta drove 

off, but Ms. E. was able to memorize part of its license plate number and called it in 

to the police immediately, at 7:24 p.m. Approximately twenty minutes later, at 7:47 

p.m., the police spotted and began to chase the white Jetta. After it crashed, they 

arrested its four fleeing occupants — Ms. Robinson, A.B., and appellants. Inside 

the car, on the back seat, the police recovered Ms. R.’s black Gucci wallet. From 

 5

 A.B. testified that Ms. Robinson gave the cell phone to Mr. Walker, who 

attempted to turn it on. Ms. Robinson, however, testified that A.B. gave it to Mr. 

Crocker, who said he could sell it. 
7

Ms. Robinson’s person, they recovered a credit card and an identification card

belonging to Ms. C. 

The police saw Mr. Walker discard a red baseball cap along with his shirt as 

he ran from the Jetta, and they recovered both items. In subsequent DNA testing of 

biological material on the cap, examiners found a match with Mr. Walker’s DNA 

profile.

The police had the wrecked Jetta towed to a lot. Four days later, the police 

released the Jetta to Mr. Hall, who visited the lot with an insurance agent and took 

photographs of the vehicle’s interior for insurance purposes. The photographs,

introduced in evidence at trial by the prosecution, showed an orange cell phone on 

the front passenger seat. At trial, Ms. C. identified the phone as hers. The photos 

also showed, among other things, a cracked iPad (which corroborated Ms. 

Robinson’s testimony that Mr. Crocker had been trying to sell such an item when he 

met her and Mr. Walker earlier in the day), and empty marijuana bags, cigar butts,

and ashes (which corroborated the testimony that the group had been smoking 

marijuana). The police never retrieved the orange cell phone or the other items seen 

in the photos. Mr. Hall testified that he left the car at the lot and received a payoff 

for it from his insurance company because the car had been “totaled.”
8

The prosecution also put in evidence data, extracted from Mr. Crocker’s GPS

ankle monitor, showing his location on the night when Mr. Hall’s Jetta was stolen 

and at the times of the robberies. The data showed that Mr. Crocker was outside Mr. 

Hall’s home at around 12:45 a.m. on August 6, 2015, and that fifteen minutes later 

he was travelling in that area at approximately twenty-five miles per hour. The GPS 

records also showed that Mr. Crocker was in the vicinity of each of the charged 

robberies at the times they were committed on August 30 and that, after the last 

reported purse snatching, he stopped at Mr. Walker’s residence for about ten 

minutes, from 7:26 to 7:36 p.m. 

In their defense at trial, both appellants attacked the credibility of Ms. 

Robinson and A.B. and denied involvement in their robberies.6

 Mr. Crocker denied 

knowing what the two women were doing when they left him in the car. Mr. Walker

claimed he did not join the group until the Jetta stopped at his residence after the last 

reported robbery already had been committed.7

 

 6

 Neither appellant testified at trial.

7

 Mr. Walker presented no evidence supporting this assertion. He argued, 

however, that it was consistent with the GPS data and Ms. Robinson’s post-arrest 

statement to police that the group was going to pick up someone she did not know

and drop that person off in Chinatown.
9

The jury found both appellants guilty of conspiracy to commit robbery, one 

count of robbery, one count of assault with intent to commit robbery, and fleeing the 

police.8 The jury also found Mr. Crocker guilty of three counts of unauthorized use 

of a vehicle during a crime of violence, receiving stolen property, destruction of 

property, and reckless driving.9

II.

Appellants argue that the release of the Jetta and its contents to Mr. Hall

violated the government’s duty under Superior Court Criminal Rule 16 to preserve 

discoverable evidence for defense inspection, and that the trial judge erred in 

denying Mr. Walker’s request for a missing evidence instruction as a sanction for 

that violation. We review this ruling for abuse of discretion, “subject to the 

 8

 In violation of D.C. Code §§ 22-1805a(a)(2), -2801 (conspiracy to commit 

robbery); 22-2801 (robbery); 22-401 (assault with intent to commit robbery); 50-

2201.05b(b)(2) (fleeing the police in a motor vehicle). The jury acquitted appellants 

of the robbery charge relating to the first purse snatching.

9

 In violation of D.C. Code §§ 22-3215(d)(2)(A) (unauthorized use of a 

vehicle during a crime of violence); 22-3232(a), (c) (receiving stolen property); 22-

303 (destruction of property); 50-2201.04 (reckless driving).
10

qualification that the proper construction of Criminal Rule 16 is a legal question as 

to which our review is de novo.”10

A. Additional Background

At appellants’ presentment in court on August 31, 2015, Mr. Walker’s counsel 

provided a “discovery and preservation” letter to the Assistant United States 

Attorney representing the government in the proceeding. The letter recited the 

government’s duty under Rule 16 to preserve material evidence for defense 

inspection. The letter did not specifically identify the Jetta or its contents as material 

and subject to preservation, however. Three days later, the police released the Jetta 

to Mr. Hall.

11 On April 10, 2017 — just before the start of trial — Mr. Walker’s 

counsel informed the trial judge that the defense intended to request a missing

evidence instruction as a sanction for the government’s failure to preserve the Jetta

for defense inspection. 

 10 Weems v. United States, 191 A.3d 296, 300 (D.C. 2018). 

11 Mr. Walker first sought an opportunity to view the Jetta, and any

“proceeds” of the robberies left in the car, in January 2016. By then the car was no 

longer in the government’s possession or available for inspection.
11

Mr. Walker submitted his proposed missing evidence instruction at the 

conclusion of the trial. The instruction stated that because “the government did not 

take sufficient steps to preserve” the Jetta or Ms. C.’s cell phone for defense 

inspection, the jury could “infer that the evidence would have been unfavorable to 

the government,” unless it concluded the evidence was duplicative or 

“unimportant.”12 The instruction said nothing about how the evidence might have 

been unfavorable to the prosecution. In the colloquy over whether to give this 

instruction, the judge pressed Mr. Walker’s counsel to explain how the missing 

 12 In its entirety, the proposed instruction read as follows:

If evidence relevant to an issue in this case was only within 

the power of one party to produce, was not produced by 

that party, and its absence has not been sufficiently 

explained, then you may, if you deem it appropriate, infer 

that the evidence would have been unfavorable to the party 

who failed to produce it. However, you should not draw 

such an inference from evidence that, in your judgment 

was equally available to both parties or which would have 

duplicated other evidence or that you think was 

unimportant. In this case, the 2006 Volkswagen Jetta was 

in the possession of the government, and the cell phone 

identified by [Ms. C.] as belonging to her in Government’s 

Exhibit 82. Both of these items were unavailable to 

defense counsel and the government did not take sufficient 

steps to preserve the items or adequately document their 

condition or contents. Thus, if you find the absence of that 

evidence not sufficiently explained, you may, if you deem 

appropriate, infer that the evidence would have been 

unfavorable to the government. 
12

evidence could have been significant for the defense. “Under your wildest dreams,” 

the judge ultimately inquired, “how would [inspection of the Jetta] have favored 

your client?” Counsel said in general terms that the car might have contained other 

evidence that the police failed to find and the photographs did not reveal, such as 

other stolen items hidden in the glove box or under the front seat. More specifically, 

counsel cited the conflicting testimony of Ms. Robinson and A.B. regarding whether 

Mr. Walker handled the orange cell phone,13 and argued that the defense could have 

retained experts to “fingerprint[] or swab[] that phone,” and to “extract[] the data 

from that phone,” to resolve that conflict. After hearing counsel out, the judge 

concluded that a missing evidence instruction was not warranted as a sanction. 

Appellants requested no other sanction for the failure to preserve the Jetta and its 

contents.

14

 13 See supra note 5.

14 The judge’s ruling left defense counsel free to argue the superficiality and 

sloppiness of the police investigation — as shown by the failure to “fingerprint the 

car” or even to search the Jetta “well enough” to find the stolen cell phone — as 

grounds for finding the government had failed to meet its burden of proof beyond a 

reasonable doubt. 
13

B. Materiality

In pertinent part, Criminal Rule 16(a)(1)(E) requires the government to 

“permit the defendant to inspect and to copy or photograph . . . tangible objects . . . 

if the item is within the government’s possession, custody, or control and: (i) the 

item is material to preparing the defense.”15 “This Rule 16 duty to permit pretrial 

discovery entails an antecedent duty to preserve material that the government has 

obtained and knows or should know is discoverable.”16 Appellants argue the Jetta 

and its contents were in the government’s possession and material to the preparation 

of their defense, and that the government violated a Rule 16 duty to preserve those 

items for their inspection by prematurely releasing the vehicle to Mr. Hall.

Appellants “bear[] the burden of establishing a prima facie case of materiality.”17

 15 Evidence in the possession of the police is within the government’s custody 

or control for purposes of Rule 16. Howard v. United States, 241 A.3d 554, 559 

(D.C. 2020).

16 Weems, 191 A.3d at 300–01. 

17 Watson v. United States, 43 A.3d 276, 283 (D.C. 2012). Given that we 

conclude appellants have shouldered their burden in that respect, we need not 

consider their alternative argument that the Jetta and its contents should have been 

preserved for defense inspection regardless of their materiality because the 

government intended to use photographs of them in its case-in-chief at trial. See 

Super. Ct. Crim. R. 16(a)(1)(E)(ii).
14

The threshold requirement of materiality “is not a high one; the defendant 

need only establish a reasonable indication that the requested evidence will either 

lead to other admissible evidence, assist the defendant in the preparation of witnesses 

or in corroborating testimony, or be useful as impeachment or rebuttal evidence.”18 

The inquiry into “[w]hether evidence is ‘material’ requires a prospective evaluation, 

from the point of view of the defendant prior to trial, of whether the evidence has 

potential value for the defendant’s development of a defense.”19 That means the 

government’s duty to preserve evidence rests, not on its own subjective 

determination that particular evidence is or is not material, but “on [the 

government’s] reasonable expectation that it will fall within the scope of evidence 

that is discoverable under Rule 16.”20

 18 Koonce v. District of Columbia, 111 A.3d 1009, 1013 (D.C. 2015) (quoting 

Tyer v. United States, 912 A.2d 1150, 1164 (D.C. 2006)); see also Howard, 241 

A.3d at 559–60. 

19 Watson, 43 A.3d at 284 (quoting Wiggins v. United States, 521 A.2d 1146, 

1148 (D.C. 1987)). Thus, the standard of materiality under Rule 16 is not as 

demanding as the post-trial due process standard of materiality that applies when the 

government has suppressed evidence favorable to the defense. See Turner v. United 

States, 116 A.3d 894, 913 (D.C. 2015) (“Evidence is material within the meaning 

of Brady ‘if there is a reasonable probability that, had the evidence been disclosed 

to the defense, the result of the proceeding would have been different.’” (quoting 

Miller v. United States, 14 A.3d 1094, 1195 (D.C. 2011)), aff’d 137 S. Ct. 1885 

(2017)).

20 Askew v. United States, 229 A.3d 1230, 1242 (D.C. 2020) (quoting Koonce, 

111 A.3d at 1017) (emphasis added in Askew). 
15

We conclude that the Jetta and its contents met Rule 16’s standard of 

materiality to the preparation of appellants’ defenses, and that from the outset the 

police and the attorneys handling the case for the government should have expected 

the car to be discoverable on that basis. Appellants were accused of using the Jetta 

in the commission of a string of robberies, and the car contained proceeds from two 

of those robberies — a wallet taken in the first robbery and a cell phone taken in the 

second. That appellants were in the Jetta with Ms. Robinson and A.B. when the 

police located it shortly after the robberies, that appellants fled from the police, and 

that Mr. Walker discarded his hat and shirt as he fled, constituted circumstantial 

evidence of their guilt. However, no victim or eyewitness to any of the robberies

identified either appellant as a participant in them or as an occupant of the Jetta at 

any time on August 30 before the police sighted it. And the police obtained no 

forensic evidence linking appellants to the robberies, no proceeds or other 

incriminating evidence from their persons, and no admissions from them. In these 

circumstances, the police and the attorneys for the government reasonably should 

have expected from the outset that appellants’ counsel would want to inspect the 

Jetta and the recovered proceeds, not merely to ascertain for themselves whether the 
16

evidence was as alleged, but also to look for evidence supporting doubt as to 

appellants’ involvement in the robberies.

21 

There conceivably could have been such evidence. Mr. Walker argues, for 

example, that a failure to find his fingerprints or DNA inside of the Jetta would have 

undercut the testimony of Ms. Robinson and A.B. that he spent the entire afternoon 

in the car with them. This might have bolstered his claim at trial that he was not 

present during the robberies because he did not join the group in the Jetta until it 

stopped at his residence after the robberies had been committed. Similarly, perhaps

the absence of Mr. Crocker’s or Mr. Walker’s fingerprints or DNA on the stolen cell 

phone could have been used to rebut the testimony of Ms. Robinson and A.B. that 

 21 At some later point prior to trial, it became clear the prosecution’s case 

against appellants would rely on the testimony of Ms. Robinson and A.B., and hence 

that appellants would be interested in discovering evidence impeaching or 

contradicting that testimony. If anything, that only confirmed the materiality of the 

Jetta and its contents to the preparation of appellants’ defenses.
17

one of them handled the phone.22 “[T]he absence of [physical] evidence is a relevant 

‘fact’ which properly [can be] argued to the jury.”23 

Citing the desirability of returning stolen property to their rightful owners 

without undue delay, the government posits that the police can satisfy Rule 16 by 

providing the defendant with “sufficiently informative photographs” of the stolen 

items in lieu of defense inspection.24 In some cases that may be so, but the 

government has not explained how any photographs taken in this case were 

“sufficiently informative” to substitute for defense inspection of the Jetta and its 

contents. Photographs obviously could not indicate the absence of fingerprints and 

DNA. 

 22 At a pretrial motions hearing in November 2016, Mr. Walker invoked his 

right under the Innocence Protection Act to request DNA testing on “the proceeds 

that were recovered from the car, as well as the proceeds that were recovered 

from . . . Ms. Robinson,” because such testing could “show that Mr. Walker never 

handled or touched those items.” By then, of course, Ms. C.’s cell phone and other 

items left in the Jetta were no longer available.

23 Greer v. United States, 697 A.2d 1207, 1210 (D.C. 1997) (alterations in 

original) (quoting United States v. Hoffman, 964 F.2d 21, 24 (D.C. Cir. 1992)). Of 

course, appellants were able to argue the absence of fingerprint and DNA evidence 

at trial due to the failure of the police to look for it. Even so, the argument might 

have seemed stronger if appellants had shown such evidence was not there to be 

found. 

24 See In re Q.D.G., 706 A.2d 36, 38 & n.6 (D.C. 1998).
18

Appellants may be unable to demonstrate exactly what inspection of the car 

would have revealed, but that does not mean they failed to carry their burden of 

showing materiality. “We recognize the force of appellant[s’] complaint that it is 

difficult to proffer the relevance of evidence that [they] cannot view.”25 That is one 

reason the standard of materiality is not a high bar and requires only a “reasonable 

indication” that the unpreserved evidence could have been useful to the defense. We 

hold that appellants have met that standard in the circumstances of this case, and that 

the government violated its duty to preserve tangible evidence material to the 

preparation of appellants’ defenses by releasing the Jetta and its contents to Mr. Hall.

 25 Howard, 241 A.3d at 562. Rule 16 disputes arising from the government’s 

failure to preserve discoverable evidence often pose such problems. See Yoon v. 

United States, 594 A.2d 1056, 1063 (D.C. 1991) (“It is impossible to know with 

certainty what effect the nondisclosure had on appellant’s pretrial planning, 

including the decision whether to seek a negotiated plea. A key purpose 

of Rule 16 is to avoid the need for such post hoc inquiry.”), amended on reh’g in 

part, 610 A.2d 1388 (D.C. 1992); cf. Vaughn v. Rosen, 484 F.2d 820, 823–24 (D.C. 

Cir. 1973) (“In a very real sense, only one side to the controversy (the side opposing 

disclosure) is in a position confidently to make statements categorizing information, 

and this case provides a classic example of such a situation.”).
19

C. Sanctions

When a trial court determines that the government violated Rule 16 by failing 

to preserve discoverable evidence, the court has discretion to choose from among an 

“extremely broad range of sanctions.”26 In deciding “what sanction, if any, to 

impose,” the court ordinarily should “weigh the degree of negligence or bad faith 

involved, the importance of the evidence lost, and the evidence of guilt adduced at 

trial[,] in order to come to a determination that will serve the ends of justice.”27 

In this case, however, the only sanction appellants requested in the trial court 

was a missing evidence instruction. And on appeal, they argue only that the court 

 26 Howard, 241 A.3d at 560 (quoting Tann v. United States, 127 A.3d 400, 

489 (D.C. 2015) (internal quotation marks omitted)).

27 Weems, 191 A.3d at 306 (alteration in original) (quoting Rodriguez v. 

United States, 915 A.2d 380, 389 (D.C. 2007)). As our cases have explained,

The deliberate destruction of evidence to hinder the 

defense generally merits severe sanction, and gross 

negligence leading to the loss of evidence usually calls for 

meaningful sanction as well. But a merely negligent or 

good faith failure to preserve discoverable evidence does 

not automatically require a trial court to impose a penalty; 

the court may excuse it and refuse to apply sanctions. 

Id. (internal quotation marks and citations omitted).
20

was required to give that instruction as a matter of law. They do not argue that the

trial court plainly erred by failing sua sponte to consider and impose an alternative, 

unrequested sanction. Accordingly, we confine our discussion to whether appellants 

were entitled to the specific sanction they sought.

28 We conclude not, because 

appellants did not satisfy the preconditions for giving a missing evidence instruction 

— preconditions this court repeatedly has insisted must be met in cases arising from 

the government’s non-preservation of discoverable evidence in violation of Rule 16.

A missing evidence instruction licenses the jury to infer that lost evidence 

would be unfavorable to a party that failed to preserve it. We have identified 

“several dangers inherent in allowing the jury to draw [that] inference,” including 

that the “inference . . . in effect creates evidence from nonevidence [and] may add a 

fictitious weight to one side of the case, for example, by giving the missing 

[evidence] undeserved significance.”29 This “‘represents a radical departure’ from 

the principle that the jury should decide the case by evaluating the evidence before 

it.”30 An additional problematic feature of missing evidence instructions, 

 28 See Howard, 241 A.3d at 560 n.4; Askew, 229 A.3d at 1246.

29 Dent v. United States, 404 A.2d 165, 170–71 (D.C. 1979). 

30 Tyer, 912 A.2d at 1164 (quoting Thomas v. United States, 447 A.2d 52, 58 

(D.C. 1982)). 
21

exemplified by the one proffered by Mr. Walker in this case, is that they afford little 

guidance to the jury in determining whether it is reasonable and appropriate to draw 

the adverse inference or not.

In light of such concerns, we have held that the trial court “retains 

considerable latitude to refuse to give a missing evidence instruction, where it 

determines from all of the circumstances that the inference of unfavorable 

evidentiary value is not a natural or reasonable one.”31 The party requesting a 

missing evidence instruction therefore “must make a twofold showing”: (1) that the 

lost evidence was “peculiarly available to the party against whom the adverse 

inference is sought to be drawn”; and (2) that the lost evidence would have been 

“likely to elucidate the transaction at issue”32 in a way that justifies drawing the 

adverse inference against that party. In other words, it must be likely that the missing 

evidence would have been “important,”33 and that it could have been unfavorable to 

 31 Howard, 241 A.3d at 561 (quoting Tyer, 912 A.2d at 1166). 

32 Tyer, 912 A.2d at 1164 (quoting Hinnant v. United States, 520 A.2d 292, 

294 (D.C. 1987)); accord Ashby v. United States, 199 A.3d 634, 647 (D.C. 2019)

(quoting Tyer, 912 A.2d at 1164); Medley v. United States, 104 A.3d 115, 132 (D.C. 

2014) (quoting Tyer, 912 A.2d at 1164).

33 See Howard, 241 A.3d at 562 (explaining that lost evidence “must have 

been ‘noncumulative’ and ‘an important part of the case’ because ‘[a]bsent these 

conditions, the logical basis for the inference evaporates, for nothing can reasonably 
22

the party responsible for its loss (or, equivalently, favorable to the party requesting 

the instruction).34 

Applying those tests, we think it clear the trial court did not abuse its 

discretion in denying Mr. Walker’s request for a missing evidence instruction. 

Although the Jetta was “peculiarly available” to the government (the police having 

seized and impounded it), appellants failed in the trial court to show the requisite 

likelihood that inspection of the vehicle could have uncovered evidence unfavorable

to the government so as to have “elucidated” the events of August 30. Mr. Walker 

argued only that examination of Ms. C.’s orange cell phone might have helped 

resolve whether he personally had handled it, and that more stolen items and other 

unspecified evidence might have been found inside the Jetta. This was nothing more 

than speculation; though it sufficed to explain why the government should have 

appreciated the potential materiality of the car and its contents to defense 

preparation, it was not enough to show a likelihood that the lost evidence actually 

 

be inferred from the failure to [present evidence that] would not be expected to 

contribute additional pertinent facts to the trial” (quoting Thomas v. United States, 

447 A.2d 52, 57 (D.C. 1982)).

34 While missing evidence also might have “elucidated” the matter in dispute 

if the evidence could have significantly benefited the party that lost it, that obviously 

would not justify instructing the jury it could infer the opposite from the loss.
23

was important enough to justify a missing evidence instruction.

35 While the 

presence of Mr. Walker’s fingerprints or DNA on the stolen cell phone, or other 

objects in the Jetta, likely would have strengthened the prosecution case, their 

absence would not have significantly weakened that case or “elucidated” whether 

Mr. Walker was present in the Jetta during the robberies. The mere absence of his 

prints and DNA on the cell phone, for example, would not have proved Mr. Walker 

never handled it.

36 Nor would it have undermined the credibility of Ms. Robinson

(who said she gave the phone to Mr. Crocker, not Mr. Walker) or disproved her 

testimony that Mr. Walker was present in the Jetta during the robberies and was a 

 35 Cf. Howard, 241 A.3d at 561 (“Assuming, without deciding, that the failure 

in this case to preserve all the contents of the backpack resulted in a violation of the 

Rule 16 duty to disclose evidence material to the defense, we discern no abuse of 

discretion in the trial court’s decision to deny the request for a missing evidence 

instruction,” given the court’s findings that there was “no bad faith on the 

government’s part” and that “a missing evidence instruction would really overstate 

the evidence.”); Tyer, 912 A.2d at 1165 (assuming a Rule 16 violation but affirming 

denial of missing evidence instruction because inspection of the evidence was 

unlikely to elucidate the transaction at issue). We do not rule out the possibility that 

Mr. Walker might have sought and obtained other meaningful sanctions; in that 

regard, we note the trial court allowed Mr. Walker to cross-examine government 

witnesses and argue that their loss of potential evidence provided reason to doubt 

the sufficiency of the government’s case against him. Cf. id. (affirming trial court’s 

denial of a missing evidence instruction and “finding it sufficient to allow defense 

counsel to question the officers about their ‘perhaps sloppy police work’”).

36 For a variety of reasons, as the government points out, fingerprints and 

DNA often are not recoverable from objects that people certainly have handled. In 

this case, for example, the police seized Mr. Walker’s shirt and Mr. Crocker’s cell

phone on August 30. They did not recover appellants’ DNA from either item.
24

co-conspirator and accomplice to them. For similar reasons, it is hardly likely that 

the retrieval of other items from the Jetta would have been unfavorable to the 

government’s case against appellants. Neither A.B. nor Ms. Robinson claimed that 

Mr. Walker touched other proceeds of their purse snatchings, nor did they say or the 

prosecution allege that he ever drove the car himself. Mr. Walker did not even argue 

in the trial court, let alone show the requisite likelihood, that a thorough search of 

the Jetta and its contents for his fingerprints and DNA could have established he was 

not long in the car on the day of the robberies. 

There is no allegation, nor reason to suppose, that the police acted in bad faith 

or had a nefarious motive for releasing the wrecked Jetta and its contents to Mr. Hall. 

This is important, for the officers’ state of mind is “key to determining whether the 

adverse inference associated with a missing evidence instruction would be ‘a natural 

or reasonable one.’”37 This is because “if an officer has acted in bad faith in 

destroying evidence, it is a more natural inference that [the officer] thought the 

 37 Howard, 241 A.3d at 561 (quoting Tyer, 912 A.2d at 1166).
25

evidence would have been harmful to the case against the defendant than if the 

officer was merely forgetful or negligent.”38

Mr. Walker argues that the police exhibited, if not bad faith or nefarious 

motive, then at least “gross indifference to or reckless disregard for the relevance of 

the evidence”39 in the Jetta to his criminal prosecution. This, he contends, was 

culpable enough to require the trial court to instruct the jury that it could infer the 

lost evidence would have been unfavorable to the prosecution. When the terms 

“gross indifference” and “reckless disregard” are used in this connection, we 

understand them to mean more than mere negligence, or even gross negligence, but 

rather “at least knowing disregard of the importance of the document to an opposing 

litigant’s claim.”40 Such knowledge is tantamount to bad faith. Yet Mr. Walker has 

not shown even gross negligence here.

 38 Id.; see also Battocchi v. Washington Hosp. Ctr., 581 A.2d 759, 766 (D.C. 

1990) (“In essence, the inference is akin to an admission by conduct of the weakness 

of one’s own case.”).

39 Battocchi, 581 A.2d at 767 (holding that, in civil cases, “upon a finding of 

gross indifference to or reckless disregard for the relevance of the evidence to a 

possible claim, the trial court must submit the issue of lost evidence to the trier of 

fact with corresponding instructions allowing an adverse inference”). 

40 Id. at 766 (“Even courts eschewing a bad faith standard have acknowledged 

that the destruction must transcend ordinary negligence, and evince at least knowing 

disregard of the importance of the document to an opposing litigant’s claim.”); cf.
26

Mr. Walker emphasizes that Metropolitan Police Department General Orders 

required the police to preserve cars used to commit robberies.

41 In the absence of a 

justification for deviating from those General Orders, this is an indication the police 

negligently breached a duty of care in releasing the Jetta to Mr. Hall when they did. 

But nothing in the record indicates more than simple negligence in the police action

here. To the contrary, we can see why the police overlooked the need to hold on to 

the Jetta for defense inspection. The police had apprehended all four of the car’s

occupants as they fled from it, so the arrestees’ presence in the vehicle did not appear 

to be in question. Whoever stole the Jetta did so without having to break into it or 

punch out its ignition, so the vehicle’s physical condition also did not appear to be 

in issue. The police had searched the Jetta once, before they towed it away, and had 

recovered from it the wallet stolen in the first robbery; there was no obvious need to 

search it again. Rather, the police had a legitimate incentive to return the Jetta 

expeditiously to its rightful owner once they no longer saw a reason to hold it.

42 The

 

Smith v. United States, 169 A.3d 887, 891, 894, 898–99 (D.C. 2017) (holding that 

trial court did not abuse its discretion by imposing lesser sanctions on government 

for grossly negligent failure to preserve evidence in violation of Criminal Rule 16).

41 See MPD General Order 304.08 (“Collection of Physical Evidence”) (April 

30, 1992) at 5–6; MPD General Order 602.01 (“Automobile Searches and 

Inventories”) (May 26, 1972) at 11.

42 See In re Q.D.G., 706 A.2d at 38 n.6. 
27

police evidently made a careless mistake in not realizing the potential materiality of 

the Jetta to defense preparation and not strictly complying with General Orders, but 

— so far as appears — it was not a grossly negligent mistake.

In Smith v. United States, this court “perceive[d] no less than gross 

negligence” where the police and the prosecutor both were careless in failing to 

preserve evidence they knew or should have known to be important and in danger of 

being lost.

43 Mr. Walker argues that this case is comparable to Smith, in that the 

 43 169 A.3d at 894. In Smith, police responding to the scene of a domestic 

dispute found Mr. Smith seated on a couch at his girlfriend’s apartment. Id. at 890. 

As Mr. Smith had no pants on at this time, his girlfriend told the officers he had a 

pair of shorts in her bedroom, though he denied they were his. Id. The police 

discovered illegal drugs in the shorts, ordered Mr. Smith to put them on, and —

instead of retaining possession of the shorts — took photographs of Mr. Smith 

wearing them. Id. Those photographs, later introduced in evidence against Mr. 

Smith to prove his possession of the drugs, appeared to show that the shorts fit him. 

Id. at 891. By then, however, the shorts had been lost. Id. at 890. At the jail

following his arrest, Mr. Smith had exchanged the shorts for prison garb, and the jail 

later destroyed them pursuant to its policy not to hold onto inmate clothing for more 

than fifteen days. Id. The loss of the shorts impaired Mr. Smith’s ability to show at 

trial that the shorts did not fit him and were not his. Id. at 896. The trial court found

that the police were negligent in not seizing the shorts. Id. at 893. This court held 

that the prosecutor was negligent, too, because, from the probable cause affidavit

proffered to the court following the arrest, the prosecutor knew of the unseized shorts 

and their evidentiary significance when they still could have been secured. Id. at 

893–94. As the trial court remarked, the “U.S. Attorney’s Office would have 

understood the evidentiary significance of those shorts” and “probably should have 

gotten a search warrant” to seize them. Id. at 893. We concluded that, based “on 

this record, given the failure [of] not just one, but two, responsible government 
28

United States Attorney’s Office carelessly failed to ensure the police preserved the 

Jetta after defense counsel served a prosecutor at Mr. Walker’s presentment with a 

letter requesting preservation of evidence. 

We disagree. The record here does not show that anyone in the United States 

Attorney’s Office was negligent or responsible for the police failure to preserve the 

Jetta. This is not a case like Smith, in which the police and the prosecutor knew or 

should have known at the time of presentment that critical evidence needed to be 

retrieved or might be lost. For one thing, the pro forma evidence preservation letter 

that defense counsel handed the prosecutor at Mr. Walker’s presentment (on which 

Mr. Walker bases his argument) did not identify the potential evidentiary 

significance of the Jetta or its contents, nor did it express any interest on the part of 

the defense in inspecting the car. The letter did not mention the Jetta at all; it merely 

recited, in general terms, the government’s Rule 16 duty to preserve material 

evidence within its possession, custody, and control. Even if the prosecutor had been 

aware of the Jetta’s potential evidentiary relevance so early in the case, the 

prosecutor would not have had reason to fear the police would fail to retain 

possession of the car. It would have been reasonable for the prosecutor to expect the 

 

departments to assure the required preservation, we perceive no less than gross 

negligence by the government.” Id. at 894 (emphasis added).
29

police to follow MPD General Orders and preserve the Jetta as a matter of course. 

The police then unexpectedly released the Jetta to Mr. Hall only three days after the 

presentment. There is no indication the police notified the United States Attorney’s 

Office before doing so, or that a prosecutor was or should have been aware the police 

might release the Jetta within that three-day period. 

For the above reasons, we hold that the trial court did not abuse its discretion 

by denying Mr. Walker’s request for a missing evidence instruction.

III.

We turn to Mr. Crocker’s claims of error. He argues that the trial judge erred 

by curtailing his cross-examination of A.B. for bias, and by permitting the prosecutor 

to vouch for the credibility of A.B. and Ms. Robinson. 

A. Cross-Examination of A.B. for Bias

Mr. Crocker claims the trial judge impermissibly prevented defense counsel 

from cross-examining A.B. about what she believed the prosecutor could do to 

disrupt her detention at the New Beginnings residential center if she did not testify 

favorably for the government. We conclude the record does not support this claim.
30

In cross-examining A.B., Mr. Walker’s counsel asked her, “You don’t want 

these prosecutors to screw . . . up [your progress at New Beginnings] for you?” A.B. 

responded, “No.” Counsel then asked A.B., “You know they can pick up the phone 

and call?” The prosecutor objected to that question as “suggest[ing] that we have 

some ability to alter her placement[,] which we have no authority to do.” In the 

bench colloquy that followed, Mr. Walker’s counsel did not dispute the prosecutor’s

assertion and said he only sought to ask A.B. whether she “believe[d] they could 

pick up the phone and call DYRS?” (Emphasis added.) The judge approved 

counsel’s rephrasing of the question, observing that if the prosecutor believed A.B. 

“came in here and perjured herself, [the prosecutor] could call[, but] we don’t know 

what the consequence of that would be.” The prosecutor asked the judge to give a 

curative instruction, “[b]ecause as it looks now it looks like [A.B.’s] a cooperator 

and like we have some ability to control.” The judge proposed to leave such an 

instruction to the end of A.B.’s testimony (saying it might be unnecessary) and 

admonished defense counsel to avoid implying that prosecutors with the United 

States Attorney’s Office “were in control of [A.B.’s] fate.”

Resuming his cross-examination, Mr. Walker’s counsel asked A.B., “You 

believe that the prosecutors can screw this up for you?” There was no objection, and 

A.B. answered, “Yes.” Then, however, defense counsel proceeded to ask A.B., 
31

“They could pick up the phone and call New Beginnings; right?” A.B. again 

answered in the affirmative, and as counsel started to ask, “They could tell them that 

—,” the judge interjected, “No. Your question is you believe.” 

At that point, the trial judge intervened to “clear this up right now” by 

instructing the jury as follows: 

Ladies and gentlemen, it’s totally appropriate for defense 

counsel to explore what the witness’ beliefs are because it 

would go to potential bias in her testimony [(emphasis 

added)]. It’s important that you understand though that 

these prosecutors are not the prosecuting officials for the 

juvenile justice system. They are not directly in control of 

anything about her commitment or that prosecution. 

Anybody, I could pick up the phone, you could pick up the 

phone. Anyone could pick up the phone and then those 

officials would decide what to do with that information 

and you could make of that what you want. But it’s just 

very important for you to understand that they’re not the 

prosecuting officials. 

But it’s also perfectly appropriate to ask questions about 

what her beliefs are [(emphasis added)]. 

The judge then addressed counsel and asked, “Is that satisfactory to everyone?” 

Defense counsel said it was satisfactory and made no objection or request at that 

time. The prosecutor likewise expressed satisfaction with the curative instruction. 
32

Defense counsel returned to questioning A.B. about what she believed the 

prosecutors could do to affect her progress at New Beginnings, and the trial court 

allowed the inquiry: 

Q. What do you think would happen if the prosecutors 

called . . . your social worker and told her that you perjured 

yourself? 

[Prosecutor]: Objection, Your Honor. 

THE COURT: Overruled [(emphasis added)].[44]

Later in the examination, defense counsel elicited another objection from the 

prosecutor by asking A.B., “You know that the U.S. Attorneys while they’re not the 

people that prosecute you in juvenile court they have more power than a regular 

person to affect what’s going on in your life; right?” Before the judge could respond 

to the objection, defense counsel undertook to rephrase it, saying “You believe that; 

correct?” The judge again allowed the inquiry, saying counsel could restate the 

whole question. Counsel then asked A.B., “You believe that these prosecutors while 

they’re not the prosecutors that prosecute juvenile court have more power than the 

average person to affect your life?”[45]

 44 A.B. responded, “I don’t know what she [her social worker] would say but 

I don’t think she would believe it.” 

45 A.B. responded, “I don’t know.” 
33

After the examination of A.B. ended and the witness was excused, Mr. 

Walker’s counsel objected to the judge’s jury instruction. Counsel did not challenge 

the instruction’s factual correctness, but asserted that it conveyed the “impression” 

that the judge was not “impartial” because the judge had “stepped outside of [her]

role and rehabilitated the witness prior to redirect by instructing the jury that these 

prosecutors don’t have any more ability to affect her life than any other person.” 

The judge disagreed.

46 However, to be sure the jury was not confused, she later 

instructed the jury as follows: 

I previously instructed you that the U.S. Attorney’s 

Office[,] the prosecutor in this case[,] is not the prosecutor 

that prosecuted the juvenile [A.B.]. Thus I told you that 

the U.S. Attorney’s Office does not directly control 

[A.B.’s] commitment. I informed you however that these 

prosecutors like anyone else could nonetheless contact 

DYRS officials with information. And it would be up to 

[those] officials to decide what to do with that information.

I also advised you that it is up to you to determine what to 

make of that situation. 

 46 Among other things, the judge pointed out that counsel did not quote the 

instruction accurately. Counsel then correctly recalled the judge merely said that 

“anyone could call up DYRS if they wanted to,” and that “these prosecutors have no 

control” over A.B.’s juvenile commitment. Counsel went on to assert that it would 

have been “proper” for the court to let the government bring those facts out in 

redirect “if they wanted to do that.” Counsel opined that the jury would have gotten 

the “impression” from the judge’s instruction that “defense counsel was engaging in 

an attempt to trick the jury or to give them the misimpression that these prosecutors 

had control.” Counsel did not substantiate this claim or the related claim of apparent 

partiality.
34

Just to be clear. What matters in this case is not influence 

the U.S. Attorney[’]s Office does or does not actually have 

with [A.B.’s] commitment. What matters is what [A.B.]

believes about what influence the U.S. Attorney’s Office 

has over her commitment [(emphasis added)]. And what 

impact if any those beliefs have on the testimony she has 

given. Those issues are for the jury to determine. 

It is clear from the record that the trial judge did not curtail defense counsel 

from pursuing a proper line of cross-examination for bias. Nor did the judge 

improperly “step outside her proper role” to “rehabilitate” A.B. on behalf of the 

government, or implicitly charge Mr. Walker’s counsel with trying to trick or 

mislead the jury. The judge simply exercised her discretionary authority “to impose 

reasonable limits on [bias] cross-examination based on concerns about, among other 

things, harassment, prejudice, confusion of the issues, the witness’ safety, or 

interrogation that is repetitive or only marginally relevant.”47 The specific concern 

 47 Austin v. United States, 64 A.3d 413, 418 (D.C. 2013) (quoting Delaware 

v. Van Arsdall, 475 U.S. 673, 679 (1986)); see also Clayborne v. United States, 751 

A.2d 956, 963 (D.C. 2000) (“The evaluation and weighing of evidence pertaining to 

bias for relevance and potential prejudice is quintessentially a discretionary function 

of the trial court, and we owe a great deal of deference to its decision. An exercise 

of judicial discretion will not be reversed unless it appears that it was exercised on 

grounds, or for reasons, clearly untenable or to an extent clearly unreasonable.” 

(cleaned up, with citations omitted)).
35

that the judge addressed here was relevancy.48 As the judge explained, the relevant 

question bearing on whether A.B. had a motive to curry favor with the prosecution 

— and the question A.B. was qualified to answer — was not the actual power vel 

non of prosecutors from the United States Attorney’s Office to affect the conditions 

of A.B.’s detention, but whether A.B. subjectively believed they had such power. 

The judge permitted defense counsel to fully explore A.B.’s beliefs on that score

(and with no judicial “rehabilitation” whatsoever of the witness). All the judge did 

was prevent counsel from conveying in his assertive questions what the judge 

reasonably feared would be a false or misleading impression that the United States 

Attorney’s Office in fact had direct control over A.B.’s commitment. In the trial 

court, Mr. Walker’s counsel did not deny that his questioning of A.B. could have 

instilled such an impression. 

Nor did defense counsel claim the federal prosecutors actually had the power

to “screw up” A.B.’s progress at New Beginnings (as Mr. Walker’s counsel put it), 

or that the judge’s curative instructions were otherwise factually erroneous. When 

the judge afforded opportunities to counsel to object to those instructions, defense 

 48 See Austin, 64 A.3d at 420 (“While evidence of bias of a principal 

prosecution witness is a proper subject of cross-examination, the proposed area for 

questioning must meet relevancy standards.”). 
36

counsel proffered no basis for a genuine belief that they were factually erroneous, or 

that the United States Attorney’s Office really could influence the conditions of 

A.B.’s detention – despite the prosecutor’s specific objection to and denial of this 

apparent premise of the cross-examination.49 Mr. Crocker asserts in his brief on 

appeal that “[a] call from a prosecutor at the U.S. Attorney’s Office does, in fact, 

likely carry greater weight with New Beginnings, than a call from a random citizen,”

and that “[t]he power of a prosecutor, who could tell the rehabilitative agency that 

their ward was not being honest in a court of law, is actually quite strong.” But Mr. 

Crocker offers nothing to justify these bare assertions (setting aside that they do not 

accurately refute what the judge actually instructed the jury), they are unsupported 

by any evidence or argument at trial, and we have no reason to accept them at face 

value.

We therefore reject Mr. Crocker’s argument that the trial judge impermissibly 

curtailed the cross-examination of A.B. for bias. 

 49 See Clayborne, 751 A.2d at 962-63 (“The examiner may not manufacture 

allegations of bias out of thin air or insinuate facts that she knows or believes are 

false. . . . The examiner must have a reasonable factual foundation, . . . or at least a 

‘well-reasoned suspicion’ that the circumstances indicating bias might be true. . . .

If opposing counsel objects to bias cross-examination based on a claimed lack of 

foundation, the examiner must proffer to the court for its evaluation the basis for her 

genuine belief that her questioning is well-grounded and hence that the answers may 

be probative of bias.”).
37

B. Impermissible Vouching

In their closing arguments, defense counsel forcefully attacked the credibility 

of A.B. and Ms. Robinson. They urged the jury not to believe A.B. because she was 

motivated to curry favor with the prosecution to avoid retribution that would 

exacerbate the conditions of her detention. As for Ms. Robinson, both defense 

counsel attacked her as a liar. Mr. Crocker’s counsel called her “in her core a 

dishonest person.” Mr. Walker’s counsel told the jury she “lied through her teeth.” 

And both counsel argued that, under Ms. Robinson’s cooperation agreement, she 

was compelled to testify to whatever the government wanted her to say was true.

In rebutting these assertions, the prosecutor made a number of statements to 

the effect that A.B. and Ms. Robinson were telling the truth. Mr. Crocker now argues 

that the prosecutor’s statements constituted impermissible prosecutorial vouching

for the witnesses’ credibility based not on the evidence at trial but on the prosecutor’s 

personal opinion. “[S]uch comments can convey the impression that evidence not 

presented to the jury, but known to the prosecutor, supports the charges against the 

defendant and can thus jeopardize the defendant’s right to be tried solely on the basis 
38

of the evidence presented to the jury.”50 It also is feared that a prosecutor’s 

expressed opinion “may induce the jury to trust the Government’s judgment rather 

than its own view of the evidence.”51 The government responds that the prosecutor’s 

statements in this case were linked to evidence supporting them and thus did not 

raise the concerns animating the prohibition on prosecutorial vouching. 

We will not exhaustively describe and evaluate each statement made by the 

prosecutor in rebuttal argument. Assuming without deciding that some of the 

prosecutor’s remarks could have been understood as inappropriate vouching for the 

credibility of A.B. or Ms. Robinson, we nonetheless reject Mr. Crocker’s claim on 

appeal. That is because his counsel did not object to the remarks at any point in the 

trial court proceedings, and his claim does not survive the rigors of plain error 

review. To obtain relief on a claim of error forfeited in the trial court, “the appellant 

[must] show that (1) the judge erred (or abused his discretion); (2) the error was clear 

or obvious; and (3) it affected the appellant’s substantial rights.”52 “If all three 

conditions are met, an appellate court may then exercise its discretion to notice a 

 50 United States v. Young, 470 U.S. 1, 18 (1985). 

51 Id. at 18–19. 

52 Simmons v. United States, 940 A.2d 1014, 1024 (D.C. 2008).
39

forfeited error, but only if (4) the error seriously affects the fairness, integrity, or 

public reputation of judicial proceedings.”53 Even assuming arguendo that the judge 

clearly erred by not intervening sua sponte in the government’s rebuttal argument 

— a dubious proposition — Mr. Crocker has not demonstrated that the judge’s 

failure to do so affected his substantial rights, i.e., that there is a “reasonable 

probability that the . . . [error] had a prejudicial effect on the outcome of his trial.”54 

Simply put, the government’s case against Mr. Crocker was overwhelming, and he 

has failed to demonstrate a reasonable probability that, absent the prosecutor’s 

alleged statements of personal opinion, the result of his trial would have been 

different.

IV. 

In sum, we hold that the trial court did not abuse its discretion in declining to 

give a missing evidence instruction as a sanction for the government’s violation of 

Criminal Rule 16. We also hold that the trial court did not curtail proper bias crossexamination or plainly err in countenancing the prosecutor’s remarks in rebuttal

argument. Accordingly, we affirm appellants’ convictions. 

 53 Id. (quoting Thomas v. United States, 914 A.2d 1, 8 (D.C. 2006)).

54 Thomas, 914 A.2d at 21.