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DISTRICT OF COLUMBIA COURT OF APPEALS

No. 17-CF-1382

ANTHONY D. HOOKS, APPELLANT

V.

UNITED STATES, APPELLEE.

Appeal from the Superior Court

of the District of Columbia

(CF2-6952-17)

(Hon. Danya A. Dayson, Trial Judge)

(Argued February 14, 2019 Decided May 30, 2019)

Christine Pembroke for appellant.

Bianca Forde, Assistant United States Attorney, for appellee. Jessie K. Liu, 

United States Attorney, and Elizabeth Trosman, John P. Mannarino, Gauri Gopal,

Puja Bhatia, and Maryam L. Adeyola, Assistant United States Attorneys, were on 

the brief for appellee. 

Before THOMPSON, EASTERLY, and MCLEESE, Associate Judges.
2

EASTERLY, Associate Judge: Anthony Hooks appeals from his convictions,

following a jury trial, for felon in possession of a weapon and related offenses.1

 

He argues that the trial court should have granted his motion to suppress the 

contraband found on his person because the police violated his rights under the 

Fourth Amendment when they seized and searched him. We agree and reverse.

I. Facts and Procedural History

On a Sunday afternoon in April 2017, Mr. Hooks attended a barbeque 

outside the home of his friend, Latisha Toney, on Congress Street Southeast. As 

the setting is relevant to the legal issues presented, we describe it in some detail. 

Ms. Toney’s residence is the end unit of a set of townhouses. From the street, her 

neighbors’ houses are to the left, and a grassy yard surrounded by a metal fence is 

to the right. Whereas all her neighbors’ front doors face Congress Street, Ms. 

Toney’s front door faces the enclosed yard. To reach Ms. Toney’s home and the 

yard from the street, a visitor must climb six steps from the sidewalk and walk 

 1

 Mr. Hooks was convicted of four crimes in all: felon in possession of a 

firearm, D.C. Code § 22-4503(a)(1), (b)(1) (2013 Supp.); possession of an 

unauthorized firearm, D.C. Code § 7-2502.01(a) (2015 Supp.); possession of a 

large capacity ammunition feeding device, D.C. Code § 7-2506.01(b) (2013 

Supp.); and unlawful possession of ammunition, D.C. Code § 7-2506.01(a)(3)

(2013 Supp.).
3

down a concrete path. The path is lined on either side by fencing that opens up on

the left to give access to another set of steps up to Ms. Toney’s front door, and on

the right to give access to the yard.

2

Having eaten some hot dogs and hamburgers, Mr. Hooks was sitting in a 

folding lawn chair on this concrete path. The other guests, a handful of adults and 

at least one child, were in the enclosed yard. Around 5:00 p.m., four police 

officers in the Narcotics Special Investigation Division drove past in an unmarked 

police car. According to the undisputed testimony of Ms. Toney, the police car

stopped a few houses past her yard and then reversed back towards her home.

Officer Dominique Tyson and three other members of his team, Officers Travis 

Collins, Brock Vigil, and Sean Hodges, all armed and in uniform, exited the 

vehicle.3

 With Officer Tyson in the lead, the four proceeded up the steps from the 

sidewalk onto the concrete pathway between Ms. Toney’s house and the enclosed 

yard, and headed straight for Mr. Hooks in his lawn chair.

 2 The concrete path continues to the rear of the row of townhouses. There is

no evidence in the record indicating that it reconnects with a public street.

3

 Officer Tyson testified at the suppression hearing that his team was on its 

way from one “buy and bust” operation to another when they “[s]aw a large group 

of males hanging out. Well, a group of individuals hanging out. Appeared to be --

some were holding cups, which was consistent with drinking alcohol, so we were 

just going to make contact with them.”
4

Officer Tyson instructed Mr. Hooks to “get up.”4 At the suppression 

hearing, Officer Tyson acknowledged he intended these two words as a command:

Q. [T]here was no question that he was going to get 

up?

A. Yes, he was going to have to move.

Q. He was going to have to move?

A. Yes.

Q. Okay. And, if he hadn't moved, you would have 

snatched him; right? You would have helped him 

move?

A. He would have got help, yes.

In response to Officer Tyson’s instruction, Mr. Hooks immediately stood up.

During this encounter, Officer Tyson observed a bag of marijuana sticking out of

Mr. Hooks’s coat pocket.

5 Based on Mr. Hooks’s admission that he was carrying a 

 4

 Officer Tyson later testified that he issued his command because he was 

concerned he would not be able to get past Mr. Hooks without bumping into him. 

He disavowed any interest in Mr. Hooks, but disagreed with defense counsel’s 

proposition that Mr. Hooks was not doing anything wrong. Officer Tyson 

explained his understanding that “In D.C., you can’t block a passage. Passage 

meaning any walkway that the public has immediate access to because you can’t 

block a walkway because someone ha[s] to walk around you[.]”

5

 The record is not entirely clear as to when Officer Tyson observed the 

drugs, but the United States has not argued in this court that he saw them before 

Mr. Hooks complied. We therefore assume for purposes of our decision that 

Officer Tyson did not see the bag until after Mr. Hooks stood up.
5

little more than two ounces of marijuana,

6 the police handcuffed Mr. Hooks, and in 

a search incident to arrest recovered a handgun.

Prior to trial, Mr. Hooks moved to suppress all tangible items seized by the 

police as fruits of an illegal seizure and search. After a hearing, the trial court 

denied the motion. The court agreed that the government had proved that either (1) 

Mr. Hooks had not been seized when the police commanded him to stand up and 

he complied, or (2) pursuant to Terry v. Ohio, 392 U.S. 1 (1968), the police had 

reasonable articulable suspicion to briefly stop Mr. Hooks because, by virtue of 

where he was sitting in his lawn chair, he was violating D.C. Code § 22-1307 

(2013 Supp.) by “obstructing [a] walkway.”

II. Standard of Review

The government introduces its discussion of our standard of review with a 

pair of statements: “[t]his Court’s review of a trial court’s denial of a motion to 

suppress is limited,” and “[t]his Court’s role in reviewing the denial of a 

 6 It is “lawful . . . for any person 21 years of age or older to . . . [p]ossess, 

use, purchase, or transport marijuana weighing 2 ounces or less.” D.C. Code § 48-

904.01(a)(1)(A) (2015 Supp.).
6

suppression motion is to ensure that the motions judge had a substantial basis for 

concluding that no constitutional violation occurred.”7

 We pause to clarify, lest 

these statements evince a misunderstanding that our analysis of constitutional 

questions under the Fourth Amendment is somehow constricted. It is not. 

Although we accept the trial court’s findings of fact unless they are clearly

erroneous and we review the facts and reasonable inferences therefrom in the light 

most favorable to the prevailing party, our review of the “trial court’s legal 

conclusions [is] de novo,” United States v. Lewis, 147 A.3d 236, 239 (D.C. 2016)

(en banc), as we have reaffirmed in countless decisions of this court,

8 including the 

cases to which the government cites.

9

 7

 The government cites Hampleton v. United States, 10 A.3d 137, 142 (D.C. 

2010), and Womack v. United States, 673 A.2d 603, 607 (D.C. 1996), for the first 

proposition, and Howard v. United States, 929 A.2d 839, 844–45 (D.C. 2007), and

Alston v. United States, 518 A.2d 439, 440 n.2 (D.C. 1986), for the second. The 

language “a substantial basis for concluding that no constitutional violation 

occurred” is actually a quotation from Howard, 929 A.2d at 844–45 (quoting 

Thompson v. United States, 745 A.2d 308, 312 (D.C. 2000)).

8

 See, e.g., Posey v. United States, 201 A.3d 1198, 1201 (D.C. 2019); Miles 

v. United States, 181 A.3d 633, 637 (D.C. 2018); Pridgen v. United States, 134 

A.3d 297, 302 (D.C. 2016); Robinson v. United States, 76 A.3d 329, 335 (D.C. 

2013).

9 Hampleton, 10 A.3d at 143 (acknowledging that our review of the legal 

question is de novo); Howard, 929 A.2d at 844 (same); Womack, 673 A.2d at 607

(same). The “substantial basis” language from Howard, 929 A.2d at 844–45, does 

not point in a different direction. Rather, that language appears to come from this 

court’s decision in Lawrence v. United States, 566 A.2d 57 (D.C. 1989), where we 

made clear that it pertains to our review of the trial court’s fact-finding: 

(continued...)
7

III. Fourth Amendment Analysis

The Fourth Amendment protects individuals against all “unreasonable 

searches and seizures.” U.S. CONST. amend. IV. “This inestimable right of 

personal security belongs as much to the citizen on the streets of our cities as to the 

homeowner closeted in his study to dispose of his secret affairs.” Terry, 392 U.S. 

at 8–9. It extends to individuals attending springtime barbeques in every quadrant 

of the District of Columbia. “For, as [the Supreme] Court has always recognized, 

[n]o right is held more sacred, or is more carefully guarded, by the common law[]

than the right of every individual to the possession and control of his own person, 

free from all restraint or interference of others, unless by clear and unquestionable 

authority of law.” Id. at 9 (internal quotation marks omitted).

 

(...continued)

We give deference to the trial judge’s findings of fact and must accept his 

resolution of conflicting testimony. Moreover, the judge’s factual findings 

will not be disturbed unless they are clearly erroneous, i.e., without 

substantial support in the record. Nevertheless, the ultimate determination 

as to whether a seizure occurred remains a question of law.

Id. at 60 (internal citations omitted) (emphasis added).
8

A. Whether Mr. Hooks Was Seized Within the Meaning of the Fourth 

Amendment

The preliminary question before us is whether the “restraint or interference” 

by the police in this case amounts to a seizure implicating Fourth Amendment 

protections. Terry, 392 U.S. at 9. As the Supreme Court explained in Terry, 

seizures are not limited to actual arrests, id. at 16–19,10 but neither do they extend 

to “all personal intercourse between policemen and citizens.” Id. at 19 n.16; 

accord Towles v. United States, 115 A.3d 1222, 1228 (D.C. 2015) (acknowledging 

that “[a] seizure does not occur simply because a law enforcement officer 

approaches a person on the street and asks him or her questions” (quoting Jackson 

v. United States, 805 A.2d 979, 984 (D.C. 2002)). The dispositive question “is 

whether, taking into account all of the circumstances surrounding the encounter, 

the police conduct would have communicated to a reasonable person that he was 

not at liberty to ignore the police presence and go about his business.”11 Florida v. 

 10 See also California v. Hodari D., 499 U.S. 621, 625–26 (1991)

(reaffirming that a seizure is not limited to an arrest and occurs when an “officer, 

by means of physical force or show of authority, has in some way restrained the 

liberty of a citizen,” so long as the individual yields to the exercise of force or 

show of authority).

11 Another formulation of the test asks whether a reasonable person would 

have felt “free to leave,” Michigan v. Chesternut, 486 U.S. 567, 573 (1988); 

Jackson, 805 A.2d at 983–84, but the protections of the Fourth Amendment extend 

to situations where a citizen has no desire to go elsewhere and instead simply 

(continued...)
9

Bostick, 501 U.S. 429, 437 (1991) (quoting Chesternut, 486 U.S. at 569); id. at 436

(“[T]he appropriate inquiry is whether a reasonable person would feel free to 

decline the officers’ requests or otherwise terminate the encounter.”); Towles, 115 

A.3d at 1228; Sharp v. United States, 132 A.3d 161, 169 (D.C. 2016) (holding 

defendant was seized “in the absence of any sign that a reasonable person in these 

circumstances would believe the officer was giving him a genuine choice to 

decline the request”). Thus, we ask whether a reasonable person in Mr. Hooks’s

position would have felt free to ignore the police officers who converged on him in 

his lawn chair, disregard their command to him to “get up,” and go about his 

business of sitting in his lawn chair. 

We conclude a reasonable person would not have felt such freedom after a 

team of four armed, uniformed officers drove past him and then reversed to get 

back to his location; all four officers emerged from the car; all four officers crossed 

the sidewalk and walked up the concrete walkway, bounded by fencing on either 

side, directly to where he was sitting in his lawn chair; and the lead officer, without 

any explanation, commanded him to “get up.” 

 

(...continued)

wishes to decline an encounter with the police. See, e.g., Florida v. Royer, 460 

U.S. 491, 493–94, 504–05 (1983) (plurality opinion) (passenger in an airport); 

Sharp, 132 A.3d at 164, 169 (individual sitting in a parked car).
10

We are guided in this determination by United States v. Mendenhall, 446 

U.S. 544 (1980) (plurality op.), where the Supreme Court provided “[e]xamples of 

circumstances that might indicate a seizure,” among them “the threatening 

presence of several officers, . . . or the use of language or tone of voice indicating 

that compliance with the officer’s request might be compelled.” Id. at 554.

12 As 

noted above, here we have both. 

We are also guided by our precedent, which requires a “realistic” assessment 

of the totality of the circumstances. Jackson, 805 A.2d at 988. Such realism 

requires the acknowledgement that “an encounter in which a visibly armed police 

officer in full uniform . . . emerges without warning from a police cruiser to 

interrupt a person going about his private business is not an encounter between 

equals. . . . The officer, however well-intentioned and polite, initiates the meeting 

with an undeniable air of authority . . . .” (Albert) Jones, 154 A.3d at 595–96

(footnote omitted).

13 “The circumstances are more intimidating . . . if more than 

 12 We do not mean to suggest that the Mendenhall factors are an exhaustive 

list; an individual may be seized even if none of them are present. E.g., (Albert)

Jones v. United States, 154 A.3d 591, 595–98 (D.C. 2017) (holding that appellant 

was seized even though the Mendenhall factors “were largely absent or of lesser 

import in th[e] case”).

13 (Albert) Jones is not at odds with Ware v. United States, 672 A.2d 557 

(D.C. 1996), cited by the government, where we observed in a footnote that “an 

(continued...)
11

one officer is present,” as was the case here.14 Id. at 596. In concluding there was 

a seizure in (Albert) Jones, we factored in the circumstance that the defendant was 

confronted by the police in a confined space, thereby “substantially reduc[ing] the 

ease with which [he] could have walked on or otherwise avoided the encounter.” 

Id. at 597. Here, Mr. Hooks’s ability to avoid an encounter with the police was 

similarly compromised; he had four armed police officers occupying the concrete 

path in front of him, a lawn chair behind him, and metal fencing to either side. In 

further comparison with (Albert) Jones, where we relied in part on the seizing 

officer’s request to view an object Mr. Jones was holding, id. at 593-98, the lead 

officer did not merely ask Mr. Hooks to allow access to an object; the officer

issued a command to Mr. Hooks to get up—a command that reasonably could have 

 

(...continued)

officer’s mere approach” does not without more constitute a seizure. Id. at 561 

n.8. Ware relied on Kelly v. United States, 580 A.2d 1282, 1285 (D.C. 1990), in 

which we explained that “it is not enough for [a defendant] to assert that police are 

inherently figures of authority, and that their presence . . . without more, convert[s] 

the encounter into a seizure.” 580 A.2d at 1285–86 (internal quotation marks 

omitted) (first emphasis added); see also Sharp, 132 A.3d at 167 (explaining that 

“Kelly is a pure questioning case”), but did not reject the premise that law 

enforcement officers wield significant power in society by virtue of their 

possession of a badge and a gun.

14 The fact that the officers were armed is “not a negligible factor bearing on 

whether a reasonable person in [Mr. Hooks’s] position would feel free to leave,”

even though they never drew their weapons. See (Albert) Jones, 154 A.3d at 595 

(citing In re J.F., 19 A.3d 304, 309 (D.C. 2011) (identifying “the visibility of the 

officers’ guns in their waistbands” as a factor in demonstrating that J.F. was 

seized)).
12

been perceived under the circumstances as a directive to submit his person to 

police control. Cf. Sharp, 132 A.3d at 169 (a reasonable person would not have 

understood the police officer’s request to the driver to “step out of the vehicle” as

“giving him a genuine choice to decline the request and stay in the car” but instead 

“conveyed a message that compliance with their request was required” (brackets

omitted)).

Based on our examination of the totality of the circumstances, we conclude 

that Mr. Hooks was, by virtue of a show of authority, seized by the police within 

the meaning of the Fourth Amendment. We are unpersuaded by the government’s 

citation to cases where this court did not find a seizure;

15 these cases are

distinguishable. This court’s decision in United States v. Barnes, 496 A.2d 1040 

(D.C. 1985), in particular does not compel a different conclusion. In Barnes, an 

 15 Brown v. United States, 983 A.2d 1023, 1025–26 (D.C. 2009) (officer 

twice asking, “in a normal tone,” from “two to three feet away” if the defendant 

possessed any contraband did not amount to a seizure); Lawrence, 566 A.2d at 63 

(single officer’s approach of a defendant walking down the sidewalk coupled with 

his question in “a calm, conversational tone of voice, [about] what [defendant] had 

in his clenched hand” was not a seizure); Richardson v. United States, 520 A.2d 

692, 697 (D.C. 1987) (single request to speak to defendant did not amount to 

seizure; defendant was only seized after he fled, discarding drugs in his 

possession); United States v. Burrell, 286 A.2d 845, 846–47 (D.C. 1972) (single 

request—“[h]old it, sir, could I speak with you a second?”—coupled with a touch 

to the elbow did not constitute a seizure).
13

officer who had seen the defendant on the street “approached [him] and asked him 

to remove his hands from his pockets,” and then asked two “nonintimidating” 

questions. Id. at 1041, 1045. We held that the defendant had not been seized

within the meaning of the Fourth Amendment because, on those facts, “nothing 

happened . . . that would have warranted appellee’s reasonable belief that he was 

not free to ignore the questions and walk away.” Id. at 1045. We cannot say the 

same of the instant case. Not only did Barnes involve a request as opposed to a 

command, the surrounding circumstances in Barnes, inter alia, the fact that the 

defendant was approached by only one officer, and “there was no . . . indication 

that [the officer] used a severe tone of voice,” were distinct. Id.

B. Whether the Police Had Reasonable Articulable Suspicion to Justify 

Mr. Hooks’s Seizure

Consistent with the Fourth Amendment, the police may, based on “probable 

cause to believe that an individual is committing or, in the case of a felony, has 

committed a crime,” conduct an arrest; alternatively, based “[u]pon a lesser 

showing of a reasonable suspicion supported by specific and articulable facts that 

the individual is involved in criminal activity[,] . . . [police] may conduct a 

correspondingly less intrusive seizure: a brief stop,” commonly referred to as a 

Terry stop, “for investigatory purposes.” Robinson, 76 A.3d at 335–36 (citations 
14

and internal quotation marks omitted). The government has never argued that the 

police had probable cause to arrest Mr. Hooks. At trial, as on appeal, its position 

was that the police had legitimate grounds to conduct a Terry stop.

Generally, when we assess whether the police conducted a valid Terry stop, 

our focus is on whether the quantum of information known to the police officer

conducting the stop amounted to reasonable, articulable, particularized suspicion

that the individual was engaged in criminal activity. See, e.g., Robinson, 76 A.3d 

at 331, 337–40. Here we need not engage in this sufficiency-type analysis, 

however, because it is clear as a matter of law that Mr. Hooks did not commit the 

crime that the government asserts the police reasonably suspected him of 

committing. 

The government argues that the officers could have reasonably believed that 

Mr. Hooks was violating the District’s anti-“crowding, obstructing, or 

incommoding” statute, D.C. Code § 22-1307.16 Based on our review of the plain 

 16 Pursuant to Devenpeck v. Alford, 543 U.S. 146, 153 (2004), the 

government was not bound by Officer Tyson’s initial reason for diverting his team 

to the enclosed yard outside Ms. Toney’s home—his apparent suspicion that her 

guests were violating the District’s open container law, see note 3 supra—and it 

has not sought to rely on this suspicion on appeal (likely because there was no 

testimony that Mr. Hooks was holding a beverage). Thus, we do not assess 

(continued...)
15

language, we disagree. D.C. Code § 22-1307(a) makes it “unlawful for a person, 

alone or in concert with others”:

(1) To crowd, obstruct, or incommode:

(A) The use of any street, avenue, alley, road, highway, or 

sidewalk;

(B) The entrance of any public or private building or enclosure;

(C) The use of or passage through any public building or public 

conveyance; or

(D) The passage through or within any park or reservation; and

(2) To continue or resume the crowding, obstructing, or incommoding 

after being instructed by a law enforcement officer to cease the 

crowding, obstructing, or incommoding.

§ 22-1307(a) (emphasis added). The statute thus plainly identifies two separate 

actus reus circumstance elements that must be satisfied before a person’s conduct 

becomes criminal. First, a person must “crowd, obstruct, or incommode” one of 

several enumerated locations, § 22-1307(a)(1)(A–D). Second, the person must 

“continue or resume the crowding, obstructing, or incommoding after being 

instructed by a law enforcement officer to cease.” § 22-1307(a)(2).17 Because 

 

(...continued)

whether that rationale would have given the police authority to seize him, although 

it is not obvious that it would. See D.C. Code § 25-1001(a) (2014 Supp.) (making 

it unlawful to possess an open container of alcohol only in specifically defined 

public spaces); Campbell v. United States, 163 A.3d 790, 795–96, 798 (D.C. 2017) 

(narrowly interpreting D.C. Code § 25-1001(a)).

17 In the section-by-section analysis of the 2012 legislation, the Judiciary 

Committee explained that certain revisions were being made to clarify some 

(continued...)
16

there is nothing in the record to indicate that, before the police seized Mr. Hooks, 

they either instructed him to cease “crowding, obstructing, or incommoding” a 

protected area under the statute, or that he disregarded such an instruction, there is 

simply no basis for any belief that Mr. Hooks was violating D.C. Code § 22-

1307.

18 

In its brief to this court, the government argues that, even if they were 

mistaken, the officers reasonably could have believed that the walkway leading to 

Ms. Toney’s front door and the enclosed yard “was covered by § 22-1307” and 

thus their seizure of Mr. Hooks could be upheld under the Supreme Court’s 

decision in Heien v. North Carolina, 135 S. Ct. 530, 536, 539 (2014) (holding that 

 

(...continued)

ambiguous language in the 2010 “Blocking Passage” statute, but that “[i]t is 

imperative, as well, to re-affirm that any of the described activity under this 

subsection [(a)(1)] is only made criminal after a law enforcement officer has 

ordered dispersal and the person (or persons) resumes or continues the same 

conduct.” D.C. Council, Report on Bill 19-645 at 42 (Nov. 29, 2012) (emphasis 

added).

18 Because we conclude that the record is devoid of any evidence to satisfy 

the second actus reus circumstance element, we do not address whether the police 

could have reasonably believed Mr. Hooks had committed the first actus reus 

circumstance element, i.e., crowding, incommoding, or obstructing the “entrance 

of any public or private building or enclosure,” under § 22-1307(a)(1)(B), the 

specific subsection relied upon by the government. Thus we avoid addressing the 

question, which was not briefed, of whether § 22-1307(a)(1)(B) either was meant 

to apply within private property or could legitimately do so.
17

“reasonable suspicion can rest on a mistaken understanding of the scope of a legal 

prohibition” so long as that misunderstanding is “objectively reasonable”). But as 

explained above, we do not resolve this case on the ground that the walkway in 

question is not covered by § 22-1307. Thus, we have no cause to say whether such 

an error would fall within the bounds of mistakes allowed by Heien. We are 

certain, however, that the officers’ suspicion that Mr. Hooks had committed a 

crime simply because he engaged in conduct described in D.C. Code § 22-

1307(a)(1)(B) is not such a mistake: It is not objectively reasonable to think that a 

person has committed a crime because the police have information indicating he 

violated half of a statute. As discussed at oral argument, no one would say that a 

person committed the crime of carrying a pistol without a license where he does 

not have a gun license, but also has no gun. Similarly here, even assuming Mr. 

Hooks was blocking a walkway “covered by § 22-1307,” the police had no basis to 

think that he was continuing to do so after being asked to disperse. We thus have 

no difficulty concluding that the Heien exception does not apply to this case.

C. Whether Suppression Is Required 

Because Mr. Hooks was seized without the requisite reasonable articulable 

suspicion, the trial court should have granted his suppression motion. It has long 

been the law that evidence collected in violation of the Fourth Amendment is 
18

considered “fruit of the poisonous tree” and generally may not be used by the 

government to prove a defendant’s guilt. Wong Sun v. United States, 371 U.S. 

471, 484, 488 (1963) (explaining the exclusionary rule deters avoidable police 

misconduct and “make[s] effective the fundamental constitutional guarantees of 

[the] sanctity of the home and inviolability of the person”); (Prince) Jones v. 

United States, 168 A.3d 703, 717 (D.C. 2017) (“[T]he exclusionary rule forbids the 

use of improperly obtained evidence at trial . . . [and] is designed to safeguard 

Fourth Amendment rights generally through its deterrent effect.” (internal 

quotation marks, citations, and alterations omitted)).

The government argues, however, that “for the same reason[]” we should 

find no Fourth Amendment violation at all under Heien, we should likewise 

conclude that application of the exclusionary rule is inappropriate in this case. We 

draw the opposite conclusion. For the same reason the police did not make a 

reasonable mistake of law, there is a strong case for deterrence through suppression 

of the contraband recovered from Mr. Hooks. The government looks to the 

Supreme Court’s decision in Herring v. United States, 555 U.S. 135 (2009). But

the factual mistake that caused the Court to reconsider the cost-benefit analysis of 

the exclusionary rule as applied in Herring is miles away from the legal error 
19

before us.

19 In Herring, the police unknowingly relied on an arrest warrant that 

had been recalled months earlier but, “because of a negligent bookkeeping error” 

by other police employees, was never deleted from a law enforcement database. 

Id. at 137–38. While cautioning that it was not “suggest[ing] that all 

recordkeeping errors by the police are immune from the exclusionary rule,” the 

Court determined that the deterrent value of suppressing evidence “obtained in 

objectively reasonable reliance on a subsequently recalled warrant” would be 

“marginal or nonexistent.” Id. at 146. By contrast, here we have a patently 

unlawful seizure by officers unaware of the letter of the law they were trying to 

enforce. The circumstances of this case are precisely those we want to deter and

amply justify the application of the exclusionary rule. See id. at 146 (rejecting the 

argument that its “decision will cause police departments to deliberately keep their 

officers ignorant” and acknowledging that the exclusionary rule should apply when 

the police behave recklessly). 

 19 Even assuming that Herring applies to mistakes of law in addition to 

mistakes of fact, because Heien postdated Herring, Herring had no cause to 

address whether unreasonable mistakes of law which are not excused under Heien,

135 S. Ct. at 539, could be exempted from the exclusionary rule.
20

As the government has not attempted to argue that the admission of the 

illegally seized contraband was harmless beyond a reasonable doubt,20 and 

harmlessness is not “obvious,”21 we reverse and remand for such further 

proceedings as are consistent with this opinion.

So ordered.

 20 See Chapman v. California, 386 U.S. 18, 24 (1967).

21 Randolph v. United States, 882 A.2d 210, 226 (D.C. 2005) (explaining 

that “it is only in the rare circumstance in which harmlessness is obvious that we 

are prepared to find an error harmless notwithstanding the government's failure to 

make a timely claim of harmlessness”).