United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued December 8, 2015 Decided March 8, 2016

No. 14–3039

UNITED STATES OF AMERICA,

APPELLEE

v.

SHERMAN MITCHELL,

APPELLANT

Consolidated with 14–3040

Appeals from the United States District Court

for the District of Columbia

(No. 1:12-cr-00258-2)

Douglas J. Behr, appointed by the court, argued the cause 

and filed the briefs for the appellant.

Elizabeth H. Danello, Assistant United States Attorney, 

argued the cause for the appellee. Vincent H. Cohen Jr., 

Acting United States Attorney, Elizabeth Trosman, John K. 

Han and Stratton C. Strand, Assistant United States Attorneys,

were with her on brief.

Before: HENDERSON and GRIFFITH, Circuit Judges, and 

RANDOLPH, Senior Circuit Judge.
2

Opinion for the Court filed by Circuit Judge HENDERSON.

KAREN LECRAFT HENDERSON, Circuit Judge: Sherman 

Mitchell (Mitchell) was convicted by jury of multiple counts of 

drug crimes resulting from his role in a phencyclidine (PCP) 

distribution ring. Mitchell challenges his convictions on 

several grounds, including, inter alia, the government’s 

purported failure to properly authenticate and demonstrate 

chain of custody for PCP samples used to establish his guilt 

and the district court’s alleged error in admitting summary 

witness evidence. We reject his challenges and affirm his 

convictions.

I. BACKGROUND

A.

In February 2012, the U.S. Drug Enforcement Agency 

(DEA), led by Special Agent Jamey Tarrh (Tarrh), opened an 

investigation into drug trafficking between California and the 

District of Columbia focused on Mitchell and his associate, 

Harvey Couser (Couser). In early May 2012, Mitchell moved 

into an apartment at the Onyx on First (Onyx) in the District of 

Columbia, which was leased by Mitchell’s half-brother,

Stephon. Although the apartment was leased in Stephon’s 

name, either Mitchell or Couser paid the rent on the apartment 

from June through November 2012 and Couser had apartment 

keys Stephon had given him. 

Between May and August 2012, Mitchell took seven 

roundtrip flights to Los Angeles, remaining there for short 

periods each time. During every trip, one or more packages 

were shipped via UPS to Mitchell’s apartment at the Onyx 

from Los Angeles, with multiple packages addressed to “Jane 

Mitchell”—“Jane” matching Mitchell’s mother’s given name. 

The government did not seize any of the packages but DEA 
3

agents observed Couser retrieving the packages addressed to 

Jane Mitchell at the Onyx several times. Specifically, on 

August 10, 2012, Tarrh’s team identified Couser entering the 

Onyx and retrieving a package shipped from Los Angeles by 

“James Campbell”—“James” matching Mitchell’s father’s

given name and “Campbell” matching Mitchell’s mother’s 

surname—to Jane Mitchell at the Onyx. The August 10, 2012

package was labelled with a contact number corresponding to a 

cell phone later seized from Couser. 

B.

Mitchell eventually moved to Los Angeles in late August 

2012, where he resided in various hotels until his arrest in 

February 2013. The shipments to the Onyx apartment from 

Los Angeles continued, with Couser retrieving multiple 

packages at the Onyx in September, October and November

2012. On November 24, two packages were shipped from 

Los Angeles to the Onyx apartment for delivery on November 

26. The two concierges at the Onyx, who cooperated with the 

ongoing investigation, notified Tarrh of the delivery of the 

packages. Tarrh asked the concierges not to deliver the 

packages to Couser until he, Tarrh, gave them permission. 

When Couser arrived at the Onyx to retrieve them, the 

concierge on duty told Couser that no package addressed to 

Mitchell’s apartment had been delivered that day. Couser 

returned to the concierge desk a few hours later and again 

requested the packages. The concierge again reported that no 

packages had been delivered and, at that point, Couser handed 

the concierge a cell phone to speak with Mitchell. Mitchell 

identified himself and excitedly explained the importance of 

the packages and asked her to contact Couser immediately 

when the packages arrived. 
4

While the delivery of the packages to Couser was delayed, 

Tarrh obtained a warrant, picked up the two packages from the 

Onyx and searched them. Inside the boxes, Tarrh found a 

total of four 64-ounce apple juice bottles filled with amber 

liquid. The bottles were delivered to Metropolitan Police 

Department (MPD) Detective Joseph Abdalla (Abdalla), who 

weighed the bottles, removed samples of the amber liquid from 

each and prepared the bottles for controlled delivery by 

refilling three of the bottles with tea and the remaining bottle 

with a mixture of tea and a small amount of the amber liquid. 

Following protocol, Abdalla then sent the remaining amber 

liquid to the MPD property division for destruction.1 Tarrh 

repacked the two boxes and returned the boxes to the Onyx for 

delivery. The next day, Mitchell telephoned the Onyx 

manager hourly about the packages until they were picked up 

by Couser once Tarrh had given permission to release them. 

When Couser returned to the Onyx to make the pick-up, 

Tarrh arrested him as he left the building. Two cell phones 

were recovered from Couser at that time. A subsequent 

search of the Onyx apartment led to the seizure of a 

money-counting machine, starter fluid, an oral syringe, a 

funnel and empty half-ounce glass vials—all tools of the PCP 

distribution trade. 

 1 The DEA laboratory subsequently tested the unmixed 

sample of amber liquid removed from one of the bottles, weighing 

1,470 grams, and determined that it contained 9.9 per cent PCP. 

This amount sufficed to support Count II of the indictment. See 

infra at 6; see also 21 U.S.C. § 841(b)(1)(A)(iv) (unlawful to possess

with intent to distribute “1 kilogram or more of a mixture or 

substance containing a detectable amount of phencyclidine”).
5

C.

Based on information obtained at Couser’s arrest, Tarrh 

and his team executed an arrest warrant for Mitchell at a 

Gardena, California hotel on February 6, 2013. 2 During 

Mitchell’s arrest, DEA agents seized a scrap of paper from his 

pocket with the name “Eric Gates” written on it. The agents 

found four cell phones in Mitchell’s hotel room, one of which 

displayed a text message with a UPS tracking number that was 

open and visible to the agents, and another scrap of paper with 

addresses for an “Eric Gates” in Gardena and a “Lisa Carter” in 

the District of Columbia. Based on this information, Corporal 

Dennis Reighard (Reighard) of the Prince George’s County 

Police Department intercepted two packages from the Prince 

George’s County UPS facility before the packages could be 

delivered to the District addresses. Reighard seized the first 

package—corresponding to the tracking number displayed on 

Mitchell’s phone at the time of his arrest—on February 8, 

2013. The package contained three 64-ounce bottles filled 

with amber liquid. As he had done with the November 2012 

package, Abdalla took samples from the bottles and the DEA 

laboratory determined that the amber liquid in one of the 

bottles, weighing 1,148 grams, contained 15.7 per cent PCP. 

Reighard seized the second package—addressed to “Lisa 

Carter” and shipped by “Eric Gates”—on February 12. This 

package contained a 32-ounce bottle filled with amber liquid. 

After Abdalla again removed a sample from the bottle, the 

DEA laboratory determined that the bottle’s amber liquid, 

weighing 776.7 grams, contained 15.9 per cent PCP. 

 2

 The record does not explain the gap between Couser’s arrest 

in November 2012 and Mitchell’s arrest in February 2013. 
6

D.

Reighard had also been involved with the seizure of a 

package before the start of the DEA investigation. On July 1, 

2011, Reighard took custody from the UPS facility in 

Burtonsville, Maryland of a package that was addressed to the 

mother of one of Mitchell’s children. The UPS security team 

had opened the package and contacted Reighard because it was 

leaking a substance with a strong odor the security team 

believed to be PCP. The package contained two one-gallon 

and four 64-ounce plastic bottles filled with amber liquid. 

Reighard stored the unopened bottles at the Prince George’s 

County Police Department until May 7, 2013, when the DEA 

connected the tracking number for the July 1, 2011 package to 

Mitchell. At that point, Abdalla removed a sample from each 

of the six bottles and the DEA laboratory, after testing one 

sample, found that the amber liquid from that bottle, weighing 

482.8 grams, contained 13.9 per cent PCP. 

E.

On April 4, 2013, Mitchell and Couser were indicted on 

one count (Count I) of conspiracy to possess with intent to 

distribute one kilogram or more of a mixture or substance 

containing PCP between February 2011 and February 2013 in 

violation of 21 U.S.C. § 841(a)(1), (b)(1)(A)(iv) and 21 U.S.C. 

§ 846 and one count (Count II) of possession with intent to 

distribute, or aiding and abetting possession with intent to 

distribute, one kilogram or more of a mixture or substance 

containing PCP on November 27, 2012 in violation of 18 

U.S.C. § 2(a) and 21 U.S.C. § 841(a)(1), (b)(1)(A)(iv). 3

 

Mitchell was further indicted on two counts of attempted 

 3

 Mitchell and Couser were also indicted on two money 

laundering counts that were dismissed pre-trial. 
7

unlawful possession with intent to distribute, aiding and 

abetting unlawful possession with intent to distribute or 

attempting to cause unlawful possession with intent to 

distribute one kilogram or more on February 8, 2013 (Count 

III) and one hundred grams or more on February 12, 2013 

(Count IV) of a mixture or substance containing PCP in 

violation of 18 U.S.C. § 2 and 21 U.S.C. § 841(a)(1), 

(b)(1)(A)(iv), (b)(1)(B)(iv). His jury trial lasted from October 

1, 2013 through October 15, 2013. On October 21, 2013, the 

jury found Couser not guilty on Counts I and II and found 

Mitchell guilty on Counts I–IV. After denying Mitchell’s 

motions for acquittal and for a new trial, the district court 

sentenced Mitchell to life imprisonment and 120 months’ 

supervised release on Counts I–III and 360 months’ 

imprisonment and 96 months’ supervised release, to run 

concurrently, on Count IV. Mitchell timely appealed. Our 

jurisdiction arises under 28 U.S.C. § 1291.

II. ANALYSIS

Mitchell raises multiple challenges to his conviction, 

almost all of which are without merit and require no further

discussion. See, e.g., United States v. Hoover-Hankerson, 

511 F.3d 164, 168 (D.C. Cir. 2007) (“[The defendants] present 

a large number of issues on appeal, not all of which deserve 

discussion.”); United States v. Thomas, 97 F.3d 1499, 1503 

(D.C. Cir. 1996) (“Thomas’s remaining contentions do not 

warrant discussion. These have been considered and 

rejected.”). We address only two arguments in full: the 

government’s alleged failure to authenticate and prove chain of 

custody for the samples of amber liquid the DEA tested for 

PCP and the government’s use of a summary witness at the end 

of its case-in-chief. 
8

A. Chain of Custody

Mitchell claims that the government failed to adequately 

authenticate and prove chain of custody for the samples tested 

at the DEA laboratory and used to show Mitchell’s 

constructive possession of the PCP. Mitchell specifically 

points to two related evidentiary gaps: (1) the government 

allegedly failed to track, with specificity, the evidence from its 

seizure by Tarrh or Reighard to Abdalla and thence to the DEA 

laboratory; and (2) the government allegedly failed to 

authenticate that the vials the DEA tested matched the samples 

Abdalla collected. Because of these gaps, Mitchell argues, 

the DEA laboratory evidence should have been excluded. We 

disagree. 

1.

We review the trial court’s admissibility rulings for abuse 

of discretion if the defendant made a timely objection and plain 

error if the defendant did not. See United States v. Coumaris, 

399 F.3d 343, 347 (D.C. Cir. 2005); see also FED. R. CRIM. P.

52(b). Mitchell claims that he objected to chain of custody 

before DEA forensic chemist John Liu (Liu) testified and again 

in his motion for acquittal. The first colloquy Mitchell relies 

on involved an objection under the Confrontation Clause. 4

 

Sherri Tupik (Tupik), a DEA chemist, initially tested the 2012 

and 2013 samples. Tupik was unavailable to testify at trial 

and, consequently, the government enlisted Liu to retest the 

samples, produce new reports and be available to testify 

regarding his reports at trial. Mitchell claimed that he should 

have had the opportunity to confront Tupik because Liu 

allegedly relied on her reports in generating his reports and his

 4

 Mitchell does not raise a Confrontation Clause challenge to 

the admissibility of the PCP testing reports on appeal.
9

reports were the only ones introduced into evidence at trial. 

Mitchell also claimed that there was inadequate chain of 

custody evidence for the period between Tupik’s and Liu’s 

reports. See, e.g., Oct. 9, 2013 Trial Tr. at 76 (“There is no 

chain of custody for [Liu’s] reports, and so there is no way to 

establish what drugs these were seized from.”); id. at 85 

(“Because they have to prove chain of custody; otherwise,

there is no evidence whatsoever that these are the drugs that 

were recovered on November 27th or sent to the DEA lab on 

the 30th other than Agent Tupik’s report that we can’t 

confront.”). Later, when the government moved to introduce 

the reports into evidence during Liu’s direct testimony, 

Mitchell objected to the reports relating to the 2012 and 2013 

samples Liu retested. 5 In arguing Couser’s motion for 

acquittal, Couser’s counsel claimed that “[t]here is absolutely 

no chain of custody in connection with the” 2012 samples 

taken by Abdalla and with Liu’s retesting reports. Oct. 10, 

2013 Trial Tr. at 163–64. Mitchell’s counsel adopted 

Couser’s “argument with respect to chain of custody.” Id. at 

167. 

The government assumes without conceding that Mitchell 

preserved a challenge to the chain of custody for the samples 

Liu retested—the 2012 and 2013 samples—but claims that we 

should review the chain-of-custody evidence of the 2011 

samples for plain error. We need not determine the applicable 

standard of review as we conclude that the district court did not 

err—whether under an abuse of discretion standard or plain 

error standard—in admitting Liu’s reports.

 5

 Mitchell did not object to the introduction of Liu’s report on

the 2011 samples because Liu was the only DEA chemist who tested 

those samples. 
10

2.

“It is generally recognized that tangible objects become 

admissible in evidence only when proof of their original 

acquisition and subsequent custody forges their connection 

with the accused and the criminal offense.”6

 United States v. 

Mejia, 597 F.3d 1329, 1335 (D.C. Cir. 2010) (quoting Gass v. 

United States, 416 F.2d 767, 770 n.8 (D.C. Cir. 1969)). The 

government has the burden to demonstrate that the “item still is 

what the [government] claims it to be.” Id. at 1336 (quoting 2 

MCCORMICK ON EVID. § 213 (6th ed. 2009)). “In order for 

evidence to be admissible, however, a complete chain of 

custody need not always be proved.” United States v. Garcia, 

757 F.3d 315, 319 (D.C. Cir. 2014) (internal quotation mark 

omitted). The proponent of the evidence need only 

“demonstrate that, as a matter of reasonable probability, 

possibilities of misidentification and adulteration have been 

eliminated.” Mejia, 597 F.3d at 1336 (internal quotation 

marks omitted). Once the evidence is admitted, a gap in the 

chain of custody goes only to the weight given to the evidence 

by the trier of fact. Garcia, 757 F.3d at 319; see also 

Melendez-Diaz v. Massachusetts, 557 U.S. 305, 311 n.1 (2009) 

(“[G]aps in the chain . . . normally go to the weight of the 

evidence rather than its admissibility.”). “A break in the chain 

 6 Mitchell claims that there are both authentication and 

chain-of-custody problems with the samples taken by Abdalla and 

tested by Liu. Here, the authentication and chain-of-custody 

concerns are one and the same—whether the samples tested by Liu 

were the same as the amber liquid in the containers seized by Tarrh 

and Reighard. We therefore proceed with a single chain-of-custody 

analysis instead of separate chain-of-custody and authentication 

analyses. Cf. FED. R. EVID. 901(a) (“To satisfy the requirement of 

authenticating or identifying an item of evidence, the proponent must 

produce evidence sufficient to support a finding that the item is what 

the proponent claims it is.”).
11

of custody,” however, “can be serious enough that the district 

court may abuse its discretion in admitting the evidence.” 

Mejia, 597 F.3d at 1336. To assess an allegedly faulty chain 

of custody, we look for “ample corroborative evidence as to 

[the evidence’s] acquisition and subsequent custody.” Id. 

The information necessary for the government to prove 

chain of custody is fairly clear. The government must

demonstrate that the jury could have “reasonably believe[d]” 

that the amber liquid contained in the various packages seized 

by Tarrh or Reighard was the same as the samples Liu tested. 

Garcia, 757 F.3d at 319. The government must have 

therefore traced the liquid from its seizure to its transfer to 

Abdalla for sampling and then to the DEA laboratory for 

testing. 

For the sample taken from the July 2011 package, 

Reighard testified that he seized the package from the UPS 

facility on July 1, 2011, and placed the contents (six bottles) in 

a labelled storage bin at the Prince George’s County Police 

Department. The bottles remained in storage there until May 

7, 2013, when, Abdalla testified, he picked them up for 

sampling. Abdalla stated that on that date he took samples 

from all six bottles, gave each sample a separate exhibit 

number and placed the samples into evidence bags labelled by 

DEA Special Agent Andy Harris (Harris). Liu testified that 

the DEA laboratory received the samples from Abdalla for 

testing on May 9, 2013, he tested one of the samples and he 

then created the report introduced at trial. For the four bottles 

contained in the two packages seized in November 2012, Tarrh 

testified that he retrieved them from the Onyx on November 

26–27, 2012. Abdalla testified that either Tarrh or DEA 

Agent Brian Mulcahy (Mulcahy), another member of the DEA 

investigative team, delivered the packages to him for sampling

on November 27. Abdalla further testified that he took five 
12

samples from the four bottles and put the samples in evidence 

bags that Mulcahy then sealed and signed. Liu explained that 

the laboratory received the samples on November 30, 2012, 

that Tupik originally tested them in May 2013 and that he 

retested them in October 2013 and prepared the reports 

introduced into evidence. And finally, for the two February 

2013 packages containing four bottles in toto, Reighard 

testified that he seized one package from the UPS facility on 

February 8 and 12, 2013, respectively. Again, Abdalla 

testified that either Tarrh or Mulcahy then delivered the 

packages to him, he sampled the four bottles, placed the 

samples in evidence bags and gave the bags to Mulcahy to seal 

and sign. Liu testified that the DEA laboratory received the 

samples on February 13, 2013, and that he eventually retested 

the samples and generated the reports introduced into 

evidence. Liu explained that he generally used the same 

procedures and analytical methods to test all samples. 

There are three gaps in the chain of custody for the 

samples Liu either tested or retested. The government 

concedes one of the gaps, Appellee’s Br. 51–52, namely, that it 

presented no evidence to explain precisely how the sealed 

evidence bags went from Abdalla to the DEA laboratory for 

testing. Id. It argues, however, that the gap is “minor” and 

goes to the weight, not admissibility, of the testing reports. Id.

at 52. We agree that this is a relatively minor gap in the chain 

of custody. For all four sets of samples, the time lag between 

Abdalla’s or Mulcahy’s sending the evidence bags to the DEA 

laboratory and the laboratory’s receipt thereof was fairly 

short—a few days at most. Further, the evidence bags were 

signed and sealed and Liu testified that he checked evidence 

bag seals for tampering before opening and retesting them. 

Liu also explained that an evidence technician put information 

about the evidence bags, including their date of delivery, into 

an internal tracking system at the time of receipt and that Liu 
13

checked the bags against the tracking system information 

before performing his analysis. We are thus convinced that 

the government met its burden to show that “as a matter of 

reasonable probability, possibilities of misidentification and 

adulteration have been eliminated” for the evidence bags from 

the time of their creation to their receipt by the DEA laboratory 

for testing. Mejia, 597 F.3d at 1336 (quoting United States v. 

Stewart, 104 F.3d 1377, 1383 (D.C. Cir. 1997)) (internal 

quotation marks omitted).

The other breaks in the chain of custody—the break 

caused by Abdalla’s apparent failure to label his samples and 

the lack of evidence regarding the creation of the evidence 

bags 7 —present closer questions. During the sampling 

process, Abdalla removed a one-ounce sample of amber liquid

from each seized bottle and placed it into a separate vial for 

each sample. Abdalla then photographed the vial next to a 

typewritten placard with identifying information; he did not, 

however, label the vials themselves. Abdalla testified that 

either he gave the one-ounce samples to Mulcahy to place into 

the labeled evidence bags or, for the 2011 samples, he and 

Harris prepared and sealed the evidence bags themselves. 

Abdalla did not identify or authenticate the evidence bags at 

trial. And although Mulcahy testified at trial, he also was not 

asked about his preparation of the evidence bags. Liu, 

however, identified the evidence bags that contained the 

samples he tested. The government therefore failed to 

introduce testimony establishing that the evidence bags 

prepared by Abdalla or Mulcahy were the ones that contained 

the samples tested by Liu—instead, Abdalla testified that he 

 7

 The evidence bags Abdallah and Mulcahy prepared held the 

sample vials. The record is unclear whether the evidence bags also 

held the bottles used to ship the liquid, except for the four bottles 

used for the November 2012 controlled delivery to Couser.
14

matched the samples with the case numbers8 given to him by 

Tarrh and with the exhibit numbers Abdalla himself generated. 

Liu then explained that generally he checked the evidence bags 

against the DEA’s internal system to make sure he was testing 

the sample with the correct case and exhibit numbers. Thus, 

the only evidence linking the vials photographed by Abdalla to 

the vials tested by Liu are the evidence bags themselves. 9 

Mulcahy and Harris should have testified that the evidence 

bags Liu authenticated were the same evidence bags they 

prepared using the samples obtained from Abdalla. The 

government thus failed to close this evidentiary gap.

 8

 The DEA assigns a case number to a particular investigation 

and an exhibit number to a specific piece of evidence collected in the 

course of that investigation. 

9

 Apart from the samples taken directly from the bottles in 

2011, 2012 and 2013, there was a potential evidentiary problem with 

a sample sent to the DEA laboratory that was purportedly removed 

from the amber liquid/tea mixture created for the November 2012 

controlled delivery. Abdalla failed to testify that he in fact removed 

a sample from the mixture before the controlled delivery. The 

government asks us to rely on a series of inferences based on the 

timing of the DEA laboratory’s testing of the samples to confirm that 

the specific report at issue corresponds to the mixed sample taken 

from the 2012 package. We need not resolve this question because 

the government met its chain-of-custody burden for the unmixed

2012 sample, see supra n.1, and therefore any error related to the 

mixed sample would be harmless. See Garcia, 757 F.3d at 319 

(“Like other evidentiary rulings, a district court’s decision to admit 

evidence over a chain-of-custody objection is subject to harmless 

error review.”); see also United States v. Johnson, 216 F.3d 1162, 

1166 n.4 (D.C. Cir. 2000) (“[N]onconstitutional error is harmless if 

it did not have ‘substantial and injurious effect or influence in 

determining the jury’s verdict.’ ” (quoting Kotteakos v. United 

States, 328 U.S. 750, 776 (1946))).
15

Nevertheless, we do not think these gaps mean that the 

district court abused its discretion in admitting Liu’s reports 

into evidence. The government had the burden to 

demonstrate that the jury could have “reasonably believe[d]” 

that the samples tested by Liu were the samples prepared by 

Abdalla. Garcia, 757 F.3d at 319. We believe the 

government met its burden, albeit not with flying colors. 

Abdalla testified that he matched each sample with its case 

number and the specific bottle seized, as demonstrated by the 

photographs showing the unlabeled sample next to an 

identifying placard. Abdalla further stated that he transferred 

the samples to Mulcahy to place into the evidence bags and the 

evidence bags—which were themselves authenticated by Liu 

and introduced into evidence—display identifying 

information, including the case number, exhibit number, date 

and location of acquisition of the sample and either Mulcahy’s 

or Harris’s signature.10 And Liu explained that he checked 

the evidence bags against the DEA’s internal tracking system 

for congruity and that the case and evidence numbers on the 

reports matched those on the evidence bags and the placards. 

This testimony and the use of identical case and exhibit 

numbers provide “ample corroborative evidence as to [the 

sample’s] acquisition and subsequent custody.” Mejia, 597 

F.3d at 1336. The jury could have reasonably concluded that 

 10 Mitchell argues that the government forfeited any reliance 

on the evidence bag labels as proof of chain of custody by failing to 

discuss the labels during trial. But during a colloquy with the 

district judge, the prosecution asserted that it relied on the case 

number as it appeared throughout the evidence—including on the 

placard in Abdalla’s photograph and on the evidence bags—to 

connect the samples Abdalla prepared to the samples Liu tested. 

Thus, even though the government did not explicitly use the labels as 

proof of chain of custody, it did rely on the case number to establish

chain of custody.
16

the samples tested by Liu were the samples prepared by 

Abdalla and packaged by Mulcahy—thus confirming a low 

probability that the samples were misidentified or adulterated. 

See generally id. at 1335–36. Although Mulcahy and Harris 

should have presented testimony about their role in preparing 

the evidence bags and Abdalla should have labelled the vials 

themselves, we conclude that the gaps in the chain of custody 

were not so substantial that the district court committed 

reversible error in admitting Liu’s reports into evidence.

B. Summary Witness

Mitchell also argues that the district court erred in 

admitting portions of DEA Investigator Lisa Amoroso’s 

(Amoroso) testimony as a summary witness. Mitchell claims 

that Amoroso exceeded the proper scope of summary witness 

testimony by improperly drawing conclusions and inferences 

from earlier–introduced evidence based on her independent 

investigation or personal opinion. Mitchell also claims the 

district court’s failure to give a limiting instruction regarding 

Amoroso’s testimony compounded the error. We find that 

any such error was harmless.

1.

To prove conspiracy, the prosecution relied on a series of 

telephone calls allegedly made by Couser or Mitchell from 

eight different phone numbers. Two numbers were tied to the

phones seized from Couser on his arrest and one was registered

in Mitchell’s name. Three numbers belonged to various 

persons named “Michael” at addresses connected to Mitchell. 

And two phone numbers were linked to default addresses 

under the name “Michael Smith” or “Del Ta.” Amoroso’s 

testimony focused on the introduction and explanation of an 

exhibit—Exhibit 30—that summarized voluminous records of 

all eight phone numbers. Exhibit 30 listed, in table form, the 
17

owner and number of the phone initiating the call;11 the date, 

time and duration of the call; and the number of the recipient 

phone and that phone’s owner and address. 

Before Amoroso testified, the prosecution and defense 

disputed the admissibility of a preliminary version of Exhibit 

30. That version included parentheticals next to the owner’s 

name that connected certain phone numbers to Couser and 

Mitchell even though those phones were registered either to 

different names or to no name at all. The prosecution asserted 

that it planned to establish links between the numbers and 

Couser or Mitchell based on Amoroso’s analysis. The 

defense objected to the introduction of a version of Exhibit 30 

that included the parentheticals, particularly because the 

parenthetical comments were derived from Amoroso’s own 

interpretation and investigation. The defense agreed to 

Exhibit 30 with the parentheticals removed and only the 

registered owners listed—counsel for both defendants stated 

that such a chart would be “consistent with what the records 

show.” Oct. 9, 2013 Trial Tr. at 239; see also id. at 239–40 

(Couser’s counsel stating “I would have no objection to the 

column that contains [the] target name and the dialed 

name . . . .”); id. at 241 (Mitchell’s counsel agreeing with 

Couser’s “position with respect to the parentheticals”). The 

government prepared a version of the table without the 

parentheticals, producing the version of Exhibit 30 introduced 

at trial. 

Amoroso then testified, connecting the relevant phone 

numbers to Couser or Mitchell through a series of inferences. 

Amoroso took the jury through each phone number at issue, 

detailing how, based on the phone records and subscriber 

 11 The table listed the owner as “NONE NONE” if there was 

no registered owner. 
18

information, it could be tied to Couser or Mitchell. For 

example, Amoroso testified that the eight phone numbers 

could be linked to Couser or Mitchell because: (1) phones 

associated with certain numbers were taken from Couser at the 

time of his arrest; or (2) the number belonged to a person who 

lived at Couser’s home address;12 or (3) the number listed one 

of Mitchell’s previous addresses or the Onyx apartment 

complex; or (4) there was an unusually large number of calls 

between the listed number and a number directly associated 

with Couser or Mitchell at the time packages were being 

shipped to the Onyx from Los Angeles. Amoroso also 

explained that she had learned during her investigation that, for 

the numbers registered to various Michaels, no one with that 

name lived at the registered address at the relevant time.

During cross-examination, Amoroso conceded that her 

conclusions were not based on information about the persons 

who in fact made the calls listed in Exhibit 30 but on the phone 

records themselves and the registered names and addresses. 

Amoroso also admitted that her information did not specify 

which apartments in the relevant complexes were connected to 

certain phone numbers. 

2.

At no point during Amoroso’s testimony did the defense 

object to the scope of her testimony. When the government 

moved to introduce Exhibit 30, the defense simply repeated its 

earlier objections, one of which unnecessarily challenged the 

content of the preliminary (and excluded) version of Exhibit 

30—and was granted—and one involved hearsay statements 

 12 The number was registered to someone living at the same 

street address as Couser but in an adjacent town where no such 

address existed. 
19

regarding the phones seized from Couser.13 Because Mitchell 

failed to object to the scope of Amoroso’s testimony, we 

review for plain error.14 See United States v. Kayode, 254 

F.3d 204, 212 (D.C. Cir. 2001); see also FED. R. CRIM. P.

52(b).

Federal Rule of Evidence 1006 permits the use of a 

“summary, chart, or calculation to prove the content of 

voluminous writings, recordings, or photographs that cannot 

be conveniently examined in court.” FED. R. EVID. 1006. A 

summary “can help the jury organize and evaluate evidence 

which is factually complex and fragmentally revealed in the 

testimony of a multitude of witnesses throughout the trial.” 

United States v. Lemire, 720 F.2d 1327, 1348 (D.C. Cir. 1983). 

To be admissible, the summary must be “accurate and 

nonprejudicial; and the witness who prepared the summary 

should introduce it.” United States v. Fahnbulleh, 752 F.3d 

470, 479 (D.C. Cir. 2014). The witness who prepared the 

 13 While testifying, Amoroso used the excluded version of 

Exhibit 30 with parentheticals to refresh her recollection. That 

version was not introduced into evidence. The defendants objected 

to its use to refresh her recollection but the court denied the objection 

because Mitchell had the opportunity to cross-examine Amoroso on 

the basis of her knowledge. The defense also objected to Amoroso 

testifying that certain phones were seized from Couser during his 

arrest, claiming it was impermissible hearsay—the district court also 

denied the objection. Mitchell does not challenge the hearsay 

objection on appeal. 

14 In his reply brief, Mitchell highlights statements made 

during the Exhibit 30 colloquy purportedly sufficient to avoid plain 

error review. See Reply Br. 20. Those statements were made in 

the context of his challenge to the parentheticals used in the first 

version of Exhibit 30. Mitchell did not raise a similar objection to 

the version of Exhibit 30 admitted into evidence and did not object to 

the scope of Amoroso’s testimony based on Exhibit 30.
20

summary may testify about how he prepared it.15 See Lemire, 

720 F.2d at 1347 (admitting “one witness’s summary of 

evidence already presented by prior witnesses”). 

We have previously limited the government’s use of 

summary evidence in particular situations. Id. at 1346–50

(permitting summary evidence but detailing problems such 

evidence can raise). The government must first lay a 

sufficient foundation for any summary evidence. See id. at 

1349. The trial judge can issue a limiting instruction 

regarding its use and cross-examination can expose 

inaccuracies or unfair characterizations. See id. at 1348. The 

summary “should not draw controversial inferences or 

pronounce[] judgment,” id. at 1350, and we have found 

overview testimony given at the beginning of the government’s 

case-in-chief prejudicial in contexts inapplicable here. United 

States v. Moore, 651 F.3d 30, 51–52 (D.C. Cir. 2011) (per 

curiam).

We conclude that even if the trial judge committed plain 

error in admitting Amoroso’s summary testimony or by failing 

to give a limiting instruction, any error was harmless. 

Although the portion of Amoroso’s testimony that was based 

on her personal investigations was detailed, Mitchell’s 

cross-examination of Amoroso helps to allay any concern. 

See Lemire, 720 F.2d at 1348 (“[A] full opportunity to 

cross-examine . . . alleviat[es] any danger of inaccuracy or 

unfair characterization.”). Amoroso inferred that certain 

phone numbers were connected to Couser or Mitchell for 

several reasons, including the frequency of calls to phones 

registered to Mitchell or taken from Couser on his arrest and 

the fact that phones were registered to addresses connected to 

 15 Our discussion is limited to a summary witness testifying 

about charts prepared and introduced under Rule 1006 and does not 

address summary witness testimony standing alone.
21

Couser or Mitchell but under different names. Amoroso 

admitted that she did independent research in concluding that 

no one living at those residences matched the name listed on 

the registration information. The use of a summary witness’s 

independent judgment, however, should be limited. See id. at 

1349 (such testimony could allow “the subtle introduction of 

otherwise inadmissible evidence” and could permit 

government extra opportunity to summarize its case-in-chief 

before closing argument “from the witness stand rather than 

the counsel’s lect[e]rn”).

Here, Amoroso’s independent investigation was fairly 

minor—she simply confirmed that no one living at the address 

to which the phone number was registered had the registered 

name. And Mitchell’s cross-examination made clear that 

Amoroso’s conclusions were based on her own inferences. 

Amoroso admitted that the phone records showed only that 

someone at one phone number called someone at another at a 

specific time. Mitchell also elicited from Amoroso a 

concession that her conclusions about the connection between 

certain addresses and Mitchell or Couser were not as clear as 

the prosecution implied on direct. Oct. 10, 2013 Trial Tr. at 

151–53. Thus, even if Amoroso’s limited testimony about her 

independent investigation was erroneously admitted, any error 

was harmless given the scope of cross examination.

Mitchell also argues that the trial judge plainly erred in 

failing to give a limiting instruction after Amoroso’s summary 

testimony. Appellant’s Br. 49–51 (citing United States v. 

Smith, 601 F.3d 530, 541 (6th Cir. 2010), United States v. 

Fullwood, 342 F.3d 409, 413 (5th Cir. 2003) and United States 

v. Johnson, 54 F.3d 1150, 1160–61 (4th Cir. 1995)). 

Whatever the merits of Mitchell’s plain error argument, any 

error was again harmless. We have recognized that “[o]ne 

danger” of summary testimony is that the “jury will treat the 
22

summary as additional evidence or as corroborative of the truth 

of the underlying testimony” and, to meet the danger, have 

characterized limiting instructions as “requisite.” Lemire, 720 

F.2d at 1348.16 Objections to summary evidence and voir dire

examination of a summary witness help protect against the risk 

that “the jury might treat the summary [witness] as substantive 

evidence.” Id. Here, the district court did exactly that—it 

allowed Mitchell to challenge and limit Exhibit 30 before its 

introduction into evidence and to conduct vigorous 

cross-examination of Amoroso. Mitchell cannot show that 

any inference Amoroso made “affected [Mitchell’s] substantial 

rights” or “seriously affect[ed] the fairness, integrity or public 

reputation of judicial proceedings,” United States v. Marcus, 

560 U.S. 258, 262 (2010), as her testimony allowed the jury to 

conclude, at most, that Mitchell attempted to hide his identity 

by using multiple phones and aliases. But even this 

conclusion does not supply the showing of prejudice or of a 

miscarriage of justice required for reversal. Nguyen v. United 

States, 539 U.S. 69, 84–85 (2003) (Rehnquist, C.J., dissenting)

(“[W]e exercise our power under Rule 52(b) sparingly . . . and 

only in those circumstances in which a miscarriage of justice 

would otherwise result.” (citations and internal quotation 

marks omitted)).

For the foregoing reasons, the judgment of the district 

court is affirmed.

So ordered.

 16 We appear to treat summary testimony and summary 

exhibits differently regarding the necessity of limiting instructions. 

See United States v. Weaver, 281 F.3d 228, 233 (D.C. Cir. 2002).