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United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued November 21, 2003 Decided June 25, 2004

No. 02-3101

UNITED STATES OF AMERICA,

APPELLEE

v.

TIMOTHY J. CRIPPEN,

APPELLANT

Appeal from the United States District Court

for the District of Columbia

(No. 02cr00075–01)

Beverly G. Dyer, Assistant Federal Public Defender, argued the cause for appellant. With her on the briefs was A.

J. Kramer, Federal Public Defender. Gregory L. Poe, Assistant Federal Public Defender, entered an appearance.

Geoffrey A. Barrow, Assistant U.S. Attorney, argued the

cause for appellee. With him on the brief were Roscoe C.

Howard, Jr., U.S. Attorney, John R. Fisher, Thomas J.

Tourish, Jr., and Ana Matheson, Assistant U.S. Attorneys.

 Bills of costs must be filed within 14 days after entry of judgment.

The court looks with disfavor upon motions to file bills of costs out

of time.
2

Before: GINSBURG, Chief Judge, and ROGERS and TATEL,

Circuit Judges.

Opinion for the Court filed by Chief Judge GINSBURG.

Separate opinion concurring in the judgment filed by Circuit Judge ROGERS.

GINSBURG, Chief Judge: A jury convicted Timothy J. Crippen of being a felon in possession of a firearm, in violation of

18 U.S.C. § 922(g)(1). Crippen challenges his conviction on

the ground that the district court erred in denying his motion

to suppress evidence, namely, guns and ammunition, seized

from his residence. Because we conclude the district court

correctly denied Crippen’s motion, we affirm his conviction.

I. Background

The Metropolitan Police Department (MPD) learned from a

confidential informant that Crippen, a convicted felon, had

several weapons in his house in northeast Washington, D.C.

The informant mentioned specifically having seen a sawed-off

shotgun and two semi-automatic pistols. Based upon this

information, Officer John Allen of the MPD’s Fifth District

sought and obtained a search warrant for the house. Before

the warrant had been executed, however, the informant told

Officer Allen that Crippen was trying to acquire a rocket

launcher. A few days thereafter, the informant reported that

he had seen a rocket launcher in Crippen’s house. He

described it as a shoulder-fired weapon consisting of a green

two-piece tube and a ‘‘flip up’’ site.

Officer Allen then asked the MPD’s Emergency Response

Team (ERT) to execute the search warrant because of ‘‘the

danger TTT of the rocket launcher.’’ During a briefing for the

ERT prior to executing the warrant, an officer demonstrated

just how quickly a rocket launcher could be armed. He also

said if the rocket launcher were fired at an officer ‘‘standing

in the doorway TTT it would go straight through [him].’’

The warrant was executed at 7:48 a.m. by a team of more

than 20 ERT officers in tactical gear. Before the officers

approached Crippen’s door, a plain-clothed animal control
3

officer entered the yard to secure Crippen’s dog. The lead

officer then knocked three times on the front door and

announced: ‘‘Police with a search warrant.’’ Four seconds

later,* police forced the door open with a battering ram and

threw a ‘‘flash bang’’ diversionary device into the house. The

officers found Crippen unarmed and asked him whether there

were weapons in the house. Crippen directed them to a 12–

gauge shotgun and a semi-automatic pistol in his bedroom

closet. The officers also found a box of 12–gauge shotgun

shells under a bed. They did not find the rocket launcher or

the second semi-automatic pistol the informant had reported

seeing.

At a pretrial hearing Crippen moved to suppress all the

evidence recovered from his home on the ground the officers

had ‘‘failed to provide a reasonable opportunity for the residents to open the door and TTT did not sufficiently announce

their authority and purpose.’’ The district court denied the

motion, holding:

[A]t the very least there were exigent circumstances that

justified the actions of the police. Those circumstances

being information received by an informant TTT relatively

shortly before the entry into the house that inside the

house were weapons including a weapon described as a

rocket launcher. A weapon TTT the dangerousness of

which was described by one of the police officer witnesses in this case. TTT Furthermore, the Court is of

the view that even if there had been TTT something

falling short of exigency, the degree to which there was a

violation of the statute would not warrant suppression of

the evidence in this case.

Crippen then entered a conditional plea of guilty, reserving

his right to appeal the denial of his motion to suppress.

* The MPD videotape of the event shows the officers waited only

four seconds before forcing entry into Crippen’s home. We find it

troubling that the police report first stated the executing officers

had waited 10 seconds before forcing entry — and more troubling

still that the report was then changed to say they had waited 40

seconds.
4

On appeal Crippen argues the district court should have

suppressed the evidence seized from his home because the

officers forced entry in violation both of the Fourth Amendment to the Constitution of the United States and of the

‘‘knock and announce’’ statute, 28 U.S.C. § 3109. He posits

the district court based its finding of exigent circumstances

solely upon the presence of dangerous weapons and thus

adopted a ‘‘categorical approach’’ inconsistent with the decision of the Supreme Court in Richards v. Wisconsin, 520 U.S.

385 (1997). The Government counters, first, the district court

properly found the circumstances were exigent and, second,

suppression of the evidence would not have been warranted

even absent an exigency.

II. Analysis

Preliminarily, we reject the Government’s argument that

we must affirm Crippen’s conviction because he has not

challenged on appeal what the Government characterizes as

the district court’s ‘‘alternative holding,’’ namely, that suppression was not warranted irrespective of the officers’ noncompliance with § 3109. The Government here relies upon

the last sentence excerpted above from the district court’s

oral opinion at the suppression hearing. That fragment is not

sufficiently reasoned to fault the defendant for not having

treated it as an independent basis for the district court’s

decision. Just as the rule of lenity requires that we interpret

an ambiguous criminal statute in the defendant’s favor, see,

e.g., United States v. Bass, 404 U.S. 336, 347–49 (1971), so

does the requirement of notice counsel against reading the

district court’s decision indulgently to the detriment of the

defendant. Cf. Smith v. O’Grady, 312 U.S. 329, 334 (1941)

(‘‘most universally recognized requirement of due process’’ is

‘‘real notice [to defendant] of the true nature of the charge

against him’’).

A. Knock and Announce

Under the Fourth Amendment and 18 U.S.C. § 3109, a law

enforcement officer may forcibly enter a residence in order to

execute a search warrant ‘‘if, after notice of his authority and
5

purpose, he is refused admittance.’’ 18 U.S.C. § 3109; see

United States v. Ramirez, 523 U.S. 65, 72–73 (1998). ‘‘[T]he

phrase ‘refused admittance’ is not restricted to an affirmative

refusal, but encompasses circumstances that constitute constructive or reasonably inferred refusal.’’ United States v.

Bonner, 874 F.2d 822, 824 (D.C. Cir. 1989). The entire

‘‘knock and announce’’ requirement ‘‘gives way,’’ however,

‘‘when officers ‘have a reasonable suspicion that knocking and

announcing their presence, under the particular circumstances, would be dangerous or futile, or TTT would inhibit the

effective investigation of the crime by, for example, allowing

the destruction of evidence.’ ’’ United States v. Banks,

U.S. , 124 S.Ct. 521, 525 (2003) (quoting Richards, 520

U.S. at 394). The standard for establishing such a reasonable

suspicion is ‘‘not high.’’ Richards, 520 U.S. at 394.

In this case it is undisputed the officers were obliged to

knock and announce their presence and purpose when executing the search warrant. It is also undisputed the officers

were not actually refused admittance to Crippen’s house, nor

did they wait long enough to infer they were being refused

admittance. The question is whether, as the Government

contends, exigent circumstances justify the officers’ decision

to force entry when they did.

B. Exigent Circumstances

In evaluating the Government’s claim of exigent circumstances we review the district court’s legal conclusions de

novo; we review its factual findings only for clear error. ‘‘A

broad range of exigent circumstances has been found to

justify less than full compliance with the various requirements of section 3109,’’ Bonner, 874 F.2d at 826, and, by

implication, of the Fourth Amendment. There are, however,

no bright-line rules or per se exceptions to the knock and

announce requirement; we must therefore evaluate each

claim of exigent circumstances upon ‘‘the facts and circumstances of the particular entry.’’ Richards, 520 U.S. at 394.

Relying upon decisions of the Sixth, Eighth, and Tenth

Circuits, Crippen maintains the anticipated presence of a

firearm on the premises to be searched cannot by itself
6

excuse the officers’ failure fully to comply with § 3109. See

United States v. Moore, 91 F.3d 96, 98 (10th Cir. 1996)

(Government must ‘‘demonstrate that the presence of firearms raised a concern for the officers’ safety’’); United States

v. Bates, 84 F.3d 790, 796 (6th Cir. 1996) (fifteen kilograms of

cocaine and potential presence of handgun insufficient to

excuse compliance with knock and announce requirement);

United States v. Marts, 986 F.2d 1216, 1218 (8th Cir. 1993)

(‘‘reasonable belief that firearms may have been within the

residence, standing alone, is clearly insufficient’’). Crippen’s

reliance upon these cases is misplaced.

In United States v. Geraldo, 271 F.3d 1112 (D.C. Cir. 2001),

after acknowledging the aforementioned decisions of the Sixth

and the Tenth Circuits, we explicitly reserved the question

whether the mere presence of a gun could be sufficient to

establish exigent circumstances. See id. at 1118. We did so

because in Geraldo itself there was more: The police were

aware the premises to be searched had been robbed a few

months earlier and that, since then, one occupant ‘‘had been

seen wearing a revolver, allegedly to protect the residence

from additional robberies.’’ Id. That information gave the

police reason to suspect knocking and announcing their purpose and then waiting to be refused admittance would be

particularly dangerous; ‘‘the agents had specific knowledge

that [the occupant] kept a firearm to protect against intruders

and therefore might be quick to use it.’’ Id.

Here, as in Geraldo, we have no occasion to decide whether

the anticipated presence of a gun could be sufficient by itself

to create an exigency excusing less than full compliance with

the requirements of the knock and announce statute and of

the Fourth Amendment. Again there is something more

involved than a mere gun.

A rocket launcher (a/k/a bazooka), is a high-powered weapon designed for use against hardened targets — such as

armored tanks, see United States v. McAnderson, 914 F.2d

934, 940 (7th Cir. 1990) — with which the MPD presumably

has little, if any, experience. The MPD was reasonably

apprehensive enough to send more than 20 members of the
7

ERT to execute the warrant specifically because of ‘‘the

danger [created by] the potential of the rocket launcher being

TTT in the house.’’ The ERT had been told that if the rocket

launcher were fired at an officer ‘‘standing in the doorway TTT

it would go straight through [him].’’ The unconventional

nature of the weapon and the speed with which it could be

loaded sufficed to create an exigency that ripened almost

immediately after the officers knocked and announced their

presence and purpose. Cf. Banks, 124 S.Ct. at 526. We

therefore conclude the search satisfied the requirements both

of the Fourth Amendment and of § 3109.

III. Conclusion

For the foregoing reasons, Crippen’s conviction is

Affirmed.
1

ROGERS, Circuit Judge, concurring in the judgment: I write

separately to clarify two points, the first regarding the analytical standard for, and the second regarding the nature of

the exigency exception to, the knock and announce requirements under 18 U.S.C. § 3109 and the Fourth Amendment.

I.

In United States v. Banks, 124 S. Ct. 521 (2003), the

Supreme Court recently addressed the analytical framework

for assessing the adequacy of police knocking and announcing

their presence when executing a warrant. The Court rejected the ‘‘overlay of a categorical scheme on the general

reasonableness analysis.’’ Id. at 528. To the extent that

United States v. Bonner, 874 F.2d 822, 826 (D.C. Cir. 1989),

and its progeny, see, e.g., United States v. Kemp, 12 F.3d

1140, 1142 (D.C. Cir. 1994), are read to create such an

overlay, positing, absent some intervening exigency, a tensecond minimum wait before police may reasonably infer

refusal of admittance, that ‘‘overgeneralization,’’ see Richards

v. Wisconsin, 520 U.S. 385, 393 (1997), can no longer survive.

What is a reasonable period of time for the police to wait

before entering pursuant to the knock and announce statute

depends on the totality of the circumstances. See Banks, 124

S. Ct. at 528; cf. United States v. Spriggs, 996 F.2d 320, 322

(D.C. Cir. 1993) (citing United States v. Davis, 617 F.2d 677,

695 (D.C. Cir. 1979)); Bonner, 874 F.2d at 825–26. After

Banks, irrespective of whether there might be potential benefits of a baseline offering specific guidance to law enforcement

officials, cf. United States v. Reid, 997 F.2d 1576, 1579 (D.C.

Cir. 1993), there is no ‘‘template’’ or ‘‘formula’’ for determining reasonableness. See Banks, 124 S. Ct. at 525 (citing GoBart Importing Co. v. United States, 282 U.S. 344, 357 (1931),

and other cases).

Consequently, whether a reasonable period of time is fifteen seconds, see Spriggs, 996 F.2d at 322–23 (cited in Banks,

124 S. Ct. at 526 n.5), more than thirty seconds, see Griffin v.

United States, 618 A.2d 114, 115, 125 (D.C. 1992), or even one

to two minutes, see United States v. Leichtnam, 948 F.2d 370,

372, 374 (7th Cir. 1991), or more or less, will depend not on
2

whether the United States Attorney prosecutes a defendant

in the federal or District of Columbia courts, but on whether

an objective experienced law enforcement officer would, under the totality of the circumstances, reasonably infer refusal

of admittance. See Bonner, 874 F.2d at 829; see also Banks,

124 S. Ct. at 527. Only if a knock and announcement is loud

enough to be heard, followed by a period long enough, in the

particular circumstances, for an occupant to answer or come

to the door, is there a constructive refusal of admittance to

the premises. See Leichtnam, 948 F.2d at 374. The duration

of this pause will vary depending on factors such as the time

of day, see Griffin, 618 A.2d at 121, the size of the premises to

which entry is sought, which may affect how long an occupant

would need to reach the door, see Bonner, 874 F.2d at 825,

whether the officers perceive light, movement, or sounds

reasonably indicating someone is up and about, see, e.g.,

Davis, 617 F.2d at 695, or whether the police had reason to

know, because they recently saw a person enter the place to

be searched, that the premises is occupied, see Griffin, 618

A.2d at 123 (citing United States v. DeLutis, 722 F.2d 902,

904 (1st Cir. 1983)). In many circumstances, ten seconds will

not be long enough for a reasonable officer to infer refusal of

admittance; therefore, the officer on the scene (and the

court) must look not to a bright line minimum time period,

but to the totality of the circumstances in determining whether there has been a constructive refusal of admittance.

II.

Of course, when an exigency arises, law enforcement officers ‘‘may go straight in.’’ Banks, 124 S. Ct. at 525. The

exigency that permits an exception to the knock and announce requirements is usually based on either of two concerns: an immediate danger to the officers executing a warrant, or a high likelihood that evidence will be destroyed or a

suspect will flee before the police will be able to gain admittance to the premises. Id. at 526. Only the former concern

is at issue here, and the government bears the burden of

showing exigent circumstances that serve to eliminate the

requirement that the police wait a reasonable period before
3

entering. Cf. United States v. Jeffers, 342 U.S. 48, 51 (1951).

As the court acknowledges, see op. at 5, the police did not

wait to be constructively denied admittance; there is no basis

to conclude from the record that the four second interval was

sufficient to allow a response from anyone inside 118 Quincy

Place, Northeast, much less to allow anyone to come to the

door. The question, therefore, is whether there were exigent

circumstances permitting the police to enter the house after

waiting only four seconds. See id.

The record indicates this case was a moving target because

the police altered the records about the time that elapsed

before they forcibly entered the premises. See op. at 3 n.*.

The government’s belated efforts to shore up its case as a

result of these vacillations possibly affected its opportunity to

flesh out the theoretical analysis for the conclusion that

exigent circumstances existed. Indeed, on appeal the government seeks refuge in a so-called alternative ruling by the

district court, an attempt that the court properly rejects. See

op. at 4. But the court, too, does not flesh out a sufficient

analysis. Finding an exigency based on the presence of an

‘‘unconventional’’ weapon that might be used against a ‘‘hardened target,’’ see op. at 6–7, would appear to decide the

question left open in United States v. Geraldo, 271 F.3d 1112,

1118 (D.C. Cir. 2001), and to threaten to create the type of

blanket exception the Supreme Court rejected in Richards.

Crippen contends that unless the government offered evidence that an occupant of 118 Quincy Place was likely to react

violently upon being confronted by the police executing a

warrant, there was no exigency because the nature of the

weapons allegedly present did not alone suffice to ‘‘present[ ]

a threat of physical violence,’’ Wilson v. Arkansas, 514 U.S.

927, 936 (1995), as viewed from the perspective of an objective, reasonable police officer. While no circuit court of

appeals has held that the mere presence of a weapon automatically creates an exigency, three circuits have held that it

does not. See United States v. Bates, 84 F.3d 790, 795 (6th

Cir. 1996); United States v. Moore, 91 F.3d 96, 98 (10th Cir.

1996); United States v. Marts, 986 F.2d 1216, 1218 (8th Cir.

1993); see also Williams v. United States, 576 A.2d 700, 706
4

(D.C. 1990) (quoting People v. Dumas, 512 P.2d 1208, 1213

(Cal. 1973)). The question is, however, open in this circuit,

see Geraldo, 271 F.3d at 1118, and the court declines now to

decide it on the ground that ‘‘something more’’ is present

here. See op. at 6.

While I agree that there is ‘‘something more’’ to this case,

the considerations relied on by the court would not suffice to

demonstrate exigent circumstances. The police had obtained

a search warrant based on an affidavit that a confidential

informant had seen ‘‘Timothy Crippen’’ with two semiautomatic pistols and a ‘‘pistol-gripped shotgun with a laser

sight’’ at 118 Quincy Place. The government does not suggest that this information sufficed to create an exigency that

obviated the need to comply with normal knock and announce

requirements. Nor did the government argue, in filing its

opposition to Crippen’s motion to suppress evidence, that an

exigency was created by the same informant’s post-warrant,

pre-search disclosure that ‘‘Timothy Crippen’’ had acquired a

rocket launcher. Instead, the government argued that ‘‘[i]t

can reasonably be inferred that the police were being denied

entry when they waited fourteen seconds and no one came to

the door.’’ The government first invoked the exigency exception only when, during the hearing on Crippen’s motion to

suppress, a videotape of the police entry revealed that the

police had broken the front door and entered the house only

four seconds after knocking and announcing, rather than the

forty seconds the police had claimed in their official report or

the fourteen seconds the United States Attorney had represented in its opposition to the motion to suppress.

The court would analogize the instant case to Geraldo,

where the police knew there was an armed gunman who

protected against robberies at a townhouse that was an active

site for drug sales and the locus for the search. See op. at 6

(citing Geraldo, 271 F.3d at 1118). Yet there is no similar

evidence suggesting that the police knew someone at 118

Quincy Place would react violently as a result of information

about recent instances in which Crippen or anyone else at the

premises had used the rocket launcher in a violent manner,
5

much less that someone had violently used or threatened to

use any of the firearms underlying the warrant. Cf. Culp v.

United States, 624 A.2d 460, 468 (D.C. 1993) (Rogers, C.J.,

concurring). In fact, the police affidavit for the search warrant indicates that the police believed the ‘‘Timothy Crippen’’

referred to by the informant was William Timothy Crippen,

appellant’s father, about whom the record lacks any evidence

of violent tendencies or a criminal history. While police

officers did testify that they believed there were two people

inside the house, they were uncertain of what precise violent

crime appellant Crippen had previously been convicted. Nor

did the police have information, as in Geraldo, about ongoing

criminal activity at the premises other than the unlawful

possession of firearms. Evidence of the presence of Crippen’s dog added nothing relevant.

The court’s reliance on the additional circumstance that

members of an urban police department may not be familiar

with a rocket launcher appears misplaced. The government

presented evidence that the police had been instructed on the

power of a projectile fired from a rocket launcher and on the

time it would take to arm the weapon. Also, the length of

time for such arming was never made part of the record, and

given the government’s burden and its special ability to

produce the evidence, cf. United States v. Hoffman, 964 F.2d

21, 24 (D.C. Cir. 1992), the absence of evidence does not

warrant an inference favorable to the government, such as

that the rocket launcher could be armed quickly so as to

threaten the police knocking on the front door of the premises. Furthermore, reliance on the police apprehension on

account of the presence of a rocket launcher, as evidenced by

the presence of more than twenty members of the Emergency Response Team to execute the warrant, carries at best

limited weight in the analysis of whether the government met

its burden to show exigent circumstances. In determining

whether there was an exigency, the court must analyze de

novo, see Ornelas v. United States, 517 U.S. 690, 699 (1996),

the reasonable suspicions of a hypothetical objective law

enforcement officer, rather than inquire into the beliefs of the

officers who actually carried out the search. See United
6

States v. Brown, 334 F.3d 1161, 1166–67 (D.C. Cir. 2003)

(citing Whren v. United States, 517 U.S. 806, 813 (1996), and

United States v. Christian, 187 F.3d 663, 670 (D.C. Cir.

1999)). Reliance on the subjective perceptions of the officers

at the scene as lending credence to the need to enter before

being denied admission would, in any event, be countered by

the testimony of the officer who breached the door that the

rocket launcher did not place the officers in ‘‘extraordinary

danger.’’

What ultimately makes this case not unlike Geraldo, and

supplies the ‘‘something more,’’ is not the presence of the

rocket launcher itself, but rather the inference that the police

could reasonably draw about Crippen from his suspected

recent acquisition of a tool of war, given the totality of

circumstances. Combined with the information about his

suspected possession of several other firearms, which are

strictly regulated in the District of Columbia, see D.C. Code

§ 22–4504, and his violent felony record, there was a reasonable basis for police officers to be apprehensive for their

safety. Crippen, because of his suspected recent acquisition

of a tool of war, could reasonably be thought by the police to

be disposed to harbor violent anti-government tendencies and

therefore to use a firearm to resist the search, had the police

waited for a longer period after announcing their presence

and purpose. The government does not make this argument

in so many words, and the evidence regarding police apprehension referred to the danger from the launching of the

rocket itself. See op. at 2. But the argument is implied from

the government’s brief that it is the combination of the illegal

firearms, the rocket launcher, Crippen’s criminal record, and

his dog that created exigent circumstances. See Respondent’s Br. at 18, 20, 21. Under the totality of the circumstances, and absent countervailing evidence either known or

that should have been known indicating that Crippen, despite

his recent acquisition of a tool of war, would not react

violently, the police did not need to have information that he

in fact had recently used firearms violently in order to

conclude that there were exigent circumstances justifying a

forced entry.
7

‘‘It is always somewhat dangerous to ground exceptions to

constitutional protections in the social norms of a given

historical moment. The purpose of the Fourth Amendment’s

requirement of reasonableness ‘is to preserve that degree of

respect for the privacy of persons and the inviolability of their

property that existed when the provision was adopted—even

if a later, less virtuous age should become accustomed to

considering all sorts of intrusion ‘‘reasonable.’’ ’ ’’ Richards,

520 U.S. at 393 n.4 (quoting Minnesota v. Dickerson, 508 U.S.

366, 380 (1993) (Scalia, J., concurring)). The knock and

announce requirements, incorporated into the Fourth Amendment and 18 U.S.C. § 3109 from the common law, see Wilson,

514 U.S. at 931–34; United States v. Ramirez, 523 U.S. 65, 73

(1998), are vital to protecting ‘‘individual privacy interests,’’

Richards, 520 U.S. at 394, including a person’s house, which

the common law viewed as ‘‘ ‘his [or her] castle of defense and

asylum.’ ’’ Wilson, 514 U.S. at 931 (citing 3 William Blackstone, Commentaries *288). Finding an exigency based on a

reasonable police conclusion concerning the violent character

of a person harboring multiple weapons, one of which is a

recently acquired tool of war, is different from finding an

exigency based on merely the presence of an ‘‘unconventional’’ weapon that might be used against a ‘‘hardened target.’’

See op. at 6–7. The former bears an analogy to Geraldo

because it informs the police about Crippen’s possibly violent

character toward government agents; the latter addresses

the question left open in Geraldo, which the court purports to

leave open. See id. The inference about Crippen’s possible

inclination to react violently, not the mere presence of a

particular weapon, is the ‘‘something more’’ from which the

court can conclude that the hasty police entry is consistent

with avoidance of both unreasonable infringement of the

interests protected by the Fourth Amendment and the type

of blanket exception the Supreme Court rejected in Richards.

Accordingly, I concur in the judgment affirming the conviction.