FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                  No. 06-10389
                Plaintiff-Appellee,
               v.                            D.C. No.
                                          CR-02-00116-1-HG
LEI SHI,
                                              OPINION
             Defendant-Appellant.
                                      
       Appeal from the United States District Court
                for the District of Hawaii
         Helen Gillmor, District Judge, Presiding

                Argued and Submitted
          November 6, 2007—Honolulu, Hawaii

                   Filed April 24, 2008

Before: Diarmuid F. O’Scannlain, A. Wallace Tashima, and
           Milan D. Smith, Jr., Circuit Judges.

              Opinion by Judge O’Scannlain




                           4367
                        UNITED STATES v. SHI                       4371
                             COUNSEL

DeAnna S. Dotson, Esq., Kapolei, Hawaii, argued the cause
for the defendant-appellant and filed briefs.

Marshall H. Silverberg, Assistant United States Attorney,
Honolulu, Hawaii, argued the cause for the plaintiff-appellee;
Thomas J. Brady, Assistant United States Attorney, Honolulu,
Hawaii, filed a brief for the plaintiff-appellee; Edward H.
Kubo, Jr., United States Attorney, District of Hawaii, Hono-
lulu, Hawaii, was on the brief.


                              OPINION

O’SCANNLAIN, Circuit Judge:

  We are called upon to decide whether a foreign national
who forcibly seizes control of a foreign vessel in international
waters may be subject to the jurisdiction of the United States
when such vessel is intercepted by federal authorities.

                                    I

                                   A

   On March 14, 2002, the Full Means No. 2, a Taiwanese
fishing vessel registered in the Republic of the Seychelles,
was sailing in international waters off the coast of Hawaii.
The Captain of the vessel was Taiwanese, while its 29 crew-
members, including Lei Shi,1 the ship’s cook, were mainland
Chinese. According to Shi, the Captain and First Mate beat
and harassed him repeatedly and, on this date, demoted Shi
  1
   There is some confusion between the parties and an ambiguity in the
record as to whether the defendant’s proper name is “Lei Shi” or “Shi
Lei.” We refer to the defendant by the former name, as it is the one most
commonly used in the papers before us.
4372                  UNITED STATES v. SHI
from the position of cook to deck hand, punctuating the deci-
sion with a beating that was particularly severe. A few hours
later, Shi responded. He retrieved two large knives from the
kitchen, ascended to the deck of the ship, and fatally stabbed
both men.

   According to the government, Shi then ordered the Second
Mate to “drive the ship” and ordered the other crewmembers
to throw the captain’s body overboard. Shi stated he would
kill anyone who disobeyed him and refused to let his fellow
crewmates use the radio. Shi retained control of the ship for
two days, setting a course for China and threatening to scuttle
the vessel if his instructions were not obeyed.

   On March 16, 2002, the crew overpowered Shi and impris-
oned him in a storage compartment on the ship. The crew then
set a course for Hawaii, though they never contacted the
ship’s parent company, apparently because none of them
knew how to operate the radio. After several days of silence,
the parent company notified the U.S. Coast Guard that the
Full Means No. 2 was missing and requested the Coast
Guard’s assistance in recovery.

   On March 19, 2002, a Coast Guard cutter intercepted the
ship approximately 60 miles from Hilo, Hawaii. Two of the
Full Means No. 2’s crewmembers set out on a raft to meet the
cutter, carrying a letter addressed to the Hawaiian government
which described Shi’s takeover. After the Republic of the
Seychelles waived jurisdiction, the ship’s acting master per-
mitted the Coast Guard to board. The Coast Guard did not
attempt to take control of the ship at the time because the offi-
cers decided first to determine whether the crew was staging
an emergency to gain entry into the United States or whether
a true exigency existed.

  Among the officers who boarded the ship was Lt. Junior
Grade Hsing-Yen John Fu, who spoke Mandarin Chinese. Lt.
Fu came upon the storage compartment where Shi was
                      UNITED STATES v. SHI                  4373
imprisoned and examined it from the outside. The crew had
sealed the door to the compartment shut by welding a metal
bar across its doorway. The door contained holes, however,
through which Fu could see Shi sitting inside. Shi’s hands
were bound behind him with wire which appeared to be cut-
ting his wrists. The compartment contained no windows or a
toilet. Fu later testified that he believed the crew fed Shi
through a hole in the door, although he did not personally wit-
ness such acts.

   Because the Coast Guard had not yet assumed control of
the vessel, the officers still considered Shi to be a prisoner of
the crew. Accordingly, they did not immediately instruct the
crew to release Shi from the compartment. Still, Lt. Fu
insisted that the crew remove the wire restraints from Shi’s
hands. The crew obliged, and the wires were replaced with
handcuffs.

   On March 19 and 20, Lt. Fu stood outside the compartment
and spoke to Shi through the holes in the door. He later testi-
fied that his decision to initiate contact with Shi was an effort
to determine whether Shi could corroborate the story told by
the crew. In the course of their exchanges, Shi told Lt. Fu that
he had killed the Captain and First Mate. Fu never read Shi
the Miranda warnings.

   On March 21 at approximately 3:00 pm, FBI agents
boarded the vessel and arrested Shi for violating 18 U.S.C.
§ 2280, which prohibits acts of violence that endanger mari-
time navigation. In addition, the agents obtained a warrant to
search Shi’s bunk area on the ship, where they discovered
several incriminating letters Shi had written to his family.

  Immediately upon releasing Shi from the storage compart-
ment, the agents allowed Shi to use the bathroom. Next, they
escorted him to the ship’s dining area, where Agent Lynelle
Torikai, through the assistance of Language Specialist Kipiu
Wun, informed Shi of the charges against him and read him
4374                 UNITED STATES v. SHI
his Miranda rights. In addition, the agents furnished Shi with
an Advice of Rights waiver written in Mandarin. Shi
expressed his willingness to answer questions, but called them
“insignificant” and did not sign the form. Agent Torikai and
Language Specialist Wun then explained the Miranda rights
and the purpose of the form for approximately five minutes,
after which Shi signed it.

   Thereafter, a Coast Guard health technician examined Shi,
treated his wrists with ointment, and wrapped them. The FBI
then transported Shi to the federal building in Honolulu,
where he was fed, permitted to use the restroom, and given a
change of clothing. At approximately 5:30 pm, Shi was
escorted to an interrogation room where Agent Torikai ques-
tioned him for approximately 4.5 hours. During such time, Shi
was fed again, permitted two smoke breaks, and confessed to
killing the Captain and First Mate.

                               B

   The government filed an indictment charging Shi with sev-
eral violations of § 2280, which proscribes certain acts of vio-
lence that endanger maritime navigation. The statute codifies
the United States’ obligations under the Convention for the
Suppression of Unlawful Acts Against the Safety of Maritime
Navigation (the “Maritime Safety Convention”), 27 I.L.M.
672 (1988), which authorizes any signatory state to extradite
or prosecute offenders, regardless of where the offender’s acts
occurred. Accordingly, § 2280 authorizes federal jurisdiction
over any offender “later found” in the United States after a
prohibited act is committed. 18 U.S.C. § 2280(b)(1)(C). In a
published order, the district court concluded that it had juris-
diction under the statute. United States v. Shi, 

(D. Haw. 2003).

  Next, the district court granted Shi’s motion to suppress his
unwarned statements to Lt. Fu on March 19 and 20, but
denied his motion to suppress his subsequent confession to
                         UNITED STATES v. SHI                         4375
Agent Torikai. The court also denied Shi’s motion to exclude
the personal letters the FBI agents seized from his bunk space,
rejecting Shi’s arguments that the warrant was invalid and
that the scope of the search was overbroad.

   Shi initially pled guilty, but soon withdrew the plea, and the
government filed a superseding indictment.2 The new indict-
ment charged Shi with one count of seizing control over a
ship by force, in violation of § 2280(a)(1)(A), and two counts
of performing an act of violence likely to endanger the safety
of the ship, in violation of § 2280(a)(1)(B). The indictment
alleged that the acts charged in all three counts “resulted in
death,” elevating the maximum statutory penalty for each
from 20 years to life in prison. The jury convicted Shi on all
counts, and the district court sentenced him to 36 years in
prison.

   Shi timely filed this appeal, challenging (1) the district
court’s jurisdiction, (2) the sufficiency of the indictment, (3)
the admissibility of his statement to Agent Torikai, (4) the
admissibility of the letters seized from his bunk, and (5) the
constitutionality of his sentence. We now turn to the merits of
these claims.

                                    II

   We begin with Shi’s contention that the district court
lacked jurisdiction because he did not meet the jurisdictional
prerequisites set forth in § 2280 and, in the alternative,
because § 2280 is unconstitutional as applied to him. We con-
sider Shi’s constitutional argument first.
  2
    Because Shi’s appeal does not implicate the initial indictment, we refer
to the first superseding indictment as “the indictment.”
4376                  UNITED STATES v. SHI
                                A

   Section 2280 codifies the United States’ obligations under
the Maritime Safety Convention to extradite or to prosecute
those who commit acts of maritime violence. Section
2280(a)(1) lists eight proscribed acts, and § 2280(b)(1) vests
federal courts with jurisdiction if certain conditions are met.
18 U.S.C. § 2280. At issue here is the provision which renders
jurisdiction proper if the “offender is later found in the United
States.” 

(emphasis added). The district
court concluded that § 2280 provided it with jurisdiction over
Shi because Shi’s arrest and transport to Honolulu rendered
him “later found” in the United States as the statute defines
that term.

                                1

   [1] Article I, Section 8, Clause 10 of the United States Con-
stitution (the “Offense Clause”) empowers Congress to “de-
fine and punish Piracies and Felonies committed on the high
Seas, and Offenses against the Law of Nations.” Because the
high seas, by definition, lie outside United States territory, see
United States v. Davis, 

, 248 (9th Cir. 1990), the
Offense Clause grants Congress the authority to apply federal
law beyond the borders of the United States, see EEOC v.
Arabian Am. Oil Co., 

, 248 (1991).

   [2] Section 2280 is an exercise of Congress’s constitutional
authority to define and punish “Felonies on the high Seas”
because it proscribes felony offenses and expressly applies to
international waters. See 18 U.S.C. § 2280(e). In addition,
§§ 2280(a)(1)(A) and (B), the provisions under which Shi was
charged, proscribe offenses which meet the definition of
piracy. “Piracy” traditionally has been defined as “robbery, or
forcible depredations upon the sea.” United States v. Smith, 

, 161 (1820). “Depredation” is “the act of plundering,
robbing, or pillaging.” Black’s Law Dictionary 397 (5th ed.
                          UNITED STATES v. SHI                           4377
1979). All three acts require the use of force.3 Section
2280(a)(1)(A) prohibits “seiz[ing] or exercis[ing] control over
a ship by force or threat thereof,” and § 2280(a)(1)(B) prohib-
its “act[s] of violence against a person on board a ship” that
are “likely to endanger the safe navigation of that ship.”
Because such offenses involve interference with property on
the open sea through the use of force, they are within Con-
gress’s power to define and to punish crimes of piracy. See

(treating “Piracies,” “Felonies on the
high Seas,” and “Offenses against the Laws of Nations” as
three separate offenses).

   [3] In addition to the Offense Clause, Congress derived the
authority to promulgate § 2280 by virtue of the Necessary and
Proper Clause. That Clause empowers Congress “to make all
Laws which shall be necessary and proper for carrying into
execution . . . all other Powers vested by this Constitution in
the Government of the United States, or in any Department or
Officer thereof.” U.S. Const. art. I, § 8, cl. 18. Such “Powers”
include the Executive’s Article II Treaty Power. See Missouri
v. Holland, 

, 432 (1920). Section 2280 imple-
ments the Maritime Safety Convention, an international
accord which requires signatory states to “prosecute or extra-
dite” offenders found within their territory regardless of
where the offense was committed. See United States v.
Yousef, 

, 95-96 (2d Cir. 2003) (per curiam) (dis-
cussing a similar provision in the Montreal Convention). In
order to satisfy this obligation, it was necessary for the United
States to codify the Convention’s “extradite or prosecute”
requirement into federal law. Section 2280 accomplishes this
  3
    The definition of “plunder” includes the taking of “property from per-
sons or places by open force.” 

(emphasis added). “Robbery”
is the “[f]elonious taking of . . . [any] article of value, in the possession
of another, from his person or immediate presence, and against his will,
accomplished by means of force or fear.” 

(emphasis added)
(citations omitted). Finally, the act of “pillaging” is the “forcible taking of
private property by an invading or conquering army from the enemy’s
subjects.” 

(emphasis added).
4378                  UNITED STATES v. SHI
task. Accordingly, the Treaty Power coupled with the Neces-
sary and Proper Clause provided Congress with an additional
source of authority to apply § 2280 beyond U.S. borders.

                               2

   [4] Congress’s constitutional authority to apply a federal
law outside U.S. borders does not end our inquiry, however,
because we may not presume that Congress intended to do so
unless it clearly expresses such intent. See Sale v. Haitian
Ctrs. Council, Inc., 

, 188 (1993). Section
2280(b)(1) applies to “covered ships,” which the statute
defines as ships “navigating or . . . scheduled to navigate into,
through or from waters beyond the outer limit of the territorial
sea of a single country,” 18 U.S.C. § 2280(e) (emphasis
added). In addition, the statute provides federal jurisdiction
over acts committed on such ships if “the offender is later
found in the United States.” 

(emphasis
added). We are satisfied that these two provisions are a clear
expression that § 2280 applies outside United States territory.

                               3

   Even if Congress had the authority to apply § 2280 beyond
the United States’ borders and clearly manifested its intent to
do so, Shi argues that the application of the statute to him vio-
lates the Due Process Clause of the Fifth Amendment. Shi
points to our decision in Davis, in which we held that when
the Maritime Drug Law Enforcement Act (“MDLEA”) is
applied to a foreign defendant apprehended on a foreign-flag
ship, due process requires “a sufficient nexus between the
defendant and the United States, so that such application
would not be arbitrary or fundamentally 

(internal citation and footnote omitted). Shi argues
that no such nexus exists here. Yet before we reach the ques-
tion of whether a jurisdictional nexus exists, we must first
determine whether such nexus is required.
                         UNITED STATES v. SHI                        4379
   [5] The Due Process Clause requires that a defendant pros-
ecuted in the United States “should reasonably anticipate
being haled into court in this country.” United States v.
Moreno-Morillo, 

, 827 (9th Cir. 2003) (internal
quotation marks and citation omitted). The MDLEA prohibits
the possession of narcotics on the high seas. Because some
states do not consider such conduct criminal, we held in Davis
that due process requires a foreign defendant apprehended on
a foreign flag ship to have some connection to the United
States before he can be prosecuted in a domestic 

. Yet in United States v. Caicedo, 

(9th Cir. 1995), we concluded that due process does not
require any such nexus when the MDLEA is applied to for-
eign defendants apprehended on stateless vessels because
“[s]uch vessels are international pariahs,” that, “by attempting
to shrug the yoke of any nation’s authority, . . . subject them-
selves to the jurisdiction of all nations.” 

(internal
quotation marks and citation omitted).

   [6] We need not determine whether the Full Means No. 2
was a foreign-flag or stateless vessel at the time it was inter-
cepted by the Coast Guard in order to resolve this case.
Instead, we abide by our instruction in Caicedo that “[a]
nexus requirement, imposed as a matter of due process, makes
sense when the ‘rough guide’ of international law also
requires a nexus.” Id.; see also 

n.2
(explaining that while not binding, “[i]nternational law princi-
ples may be useful as a rough guide of whether a sufficient
nexus exists between the defendant and the United States”).

   [7] In applying the “rough guide” of international law, we
turn to the principle of universal jurisdiction. Universal juris-
diction is based on the premise that offenses against all states
may be punished by any state where the offender is found. See
  4
   Such nexus would be established, for example, if the foreign defen-
dant’s extraterritorial conduct is purposefully aimed at the United States.
See, e.g., United States v. Aikins, 

, 613-14 (9th Cir. 1990).
4380                 UNITED STATES v. SHI
Stephen Macedo, Universal Jurisdiction 2-12 (2004). Accord-
ingly, it allows a state to claim jurisdiction over such an
offender even if the offender’s acts occurred outside its
boundaries and even if the offender has no connection to the
state.

   As explained above, the acts with which Shi is charged
constitute acts of piracy. See supra at 4376-77. Prosecuting
piracy was the original rationale for creating universal juris-
diction, see, e.g., Kenneth C. Randall, Universal Jurisdiction
Under International Law, 

, 803 (1988)
(citing piracy as the “archetypal universal crime”), and federal
courts have historically accepted the notion that a pirate may
be tried by any state, see 

(“piracy . . .
is an offense against the universal law of society, a pirate
being, according to Sir Edward Coke, hostis humani generis
[an enemy of the human race]”) (quoting 4 Blackstone’s Com-
mentaries *71, 73). Due process does not require a nexus
between such an offender and the United States because the
universal condemnation of the offender’s conduct puts him on
notice that his acts will be prosecuted by any state where he
is found. See United States v. Martinez-Hidalgo, 

, 1056 (3d Cir. 1993) (holding that inasmuch as a crime
is “condemned universally by law-abiding nations, we see no
reason to conclude that it is ‘fundamentally unfair’ for Con-
gress to provide for the punishment” of offenders appre-
hended on the high seas).

  [8] Sections 2280(a)(1)(A) and (B) prohibit interference
with the safe navigation of a maritime vessel through the use
or threat of force. Because these are acts of piracy, and
because such acts are universally condemned, due process
does not require the same nexus between the offender and the
United States as does the MDLEA.

   Moreover, due process does not require the same nexus
between violators of § 2280 and the United States because
§ 2280 implements the Maritime Safety Convention, which
                           UNITED STATES v. SHI                            4381
expressly provides foreign offenders with notice that their
conduct will be prosecuted by any state signatory.5 We
acknowledge that in a similar case, the Second Circuit sug-
gested that a jurisdictional nexus was required. In Yousef, a
foreign national apprehended abroad was prosecuted in the
United States for violating 18 U.S.C. § 32(b), which prohibits
aircraft piracy, after he hijacked a Philippine Airlines 

. The Second Circuit cited our decision in
Davis, which applied a nexus requirement to a foreign defen-
dant apprehended abroad and prosecuted under the MDLEA.

The court reasoned that such requirement was met
in Yousef’s case because his conduct was purposefully aimed
at the United States: he previously hijacked aircrafts in the
United States and his hijacking of the Philippine Airlines
flight was a test-run for an attack in this country. 

12.

   The court’s treatment of the due process question consisted
of only three paragraphs of a 147-page opinion, however, and
while the court cited our decision, 

(citing 

), it never considered the implications of our
refusal to extend the nexus requirement to foreign defendants
apprehended on stateless vessels in Moreno-Morillo and
Caicedo. See 

; 

. Those decisions suggest that a nexus is not
required when the offender’s conduct is proscribed univer-
sally.
   5
     This is not to suggest that the Convention creates “universal jurisdic-
tion” over the crimes it proscribes. As the Second Circuit explained in
interpreting an identical “extradite or prosecute” provision, “[w]hile the
purpose of such treaties is to assure ‘universal punishment of the offenses
in question’ . . . it is incorrect to speak of these treaties as creating ‘univer-
sal jurisdiction,’ or even ‘treaty-based universal jurisdiction,’ because the
treaties create obligations only in States party to them, not universally in
all states.” 

n.29 (interpreting a nearly identical pro-
vision in the Montreal Convention). Instead, such accords amount to “ju-
risdictional agreement[s] among contracting States to extradite or
prosecute offenders.” 

4382                  UNITED STATES v. SHI
   The D.C. Circuit’s decision United States v. Rezaq, 

(D.C. Cir. 1998), supports such conclusion. In that
case, a foreign national was apprehended abroad and charged
with hijacking an Air Egypt flight in violation of 49 U.S.C.
app. § 1472(n) (1994). 

The D.C. Circuit con-
cluded that federal jurisdiction over Rezaq was proper without
noting any possible due process concerns. Although the
court’s silence may have stemmed from any number of rea-
sons, it is important to note that, like § 2280, the statute in
Rezaq was enacted to implement an international agreement
to extradite and to prosecute perpetrators of widely-
condemned conduct. (Section 1472(n) implemented the
Hague Convention, which prohibits aircraft hijacking.)

   [9] Congress’s authority to apply § 2280 beyond United
States borders stems in part from its power under the Offense
Clause to punish “Piracies on the high Seas,” not merely “Fel-
onies,” as Congress has done in statutes such as the MDLEA.
Because piracy is a universally-condemned crime, a jurisdic-
tional nexus is not required to satisfy due process. As such,
we conclude that the universal condemnation of Shi’s conduct
and the existence of the Maritime Safety Convention provided
him with all the notice due process requires that he could be
prosecuted in this country. Accordingly, the district court’s
exercise of jurisdiction over Shi was “neither arbitrary nor
fundamentally unfair.” 

n.7
(citing 

).

                                B

   Having established that the district court’s exercise of juris-
diction over Shi satisfied the Constitution’s requirements, we
next consider Shi’s arguments that jurisdiction was improper
under the statutory requirements set forth in § 2280, which
permits jurisdiction if the “offender is later found in the
United States.” 

(emphasis added). The
government contends that Shi’s arrest and transport to the
                          UNITED STATES v. SHI                         4383
Honolulu federal building brought him within the terms of
this provision. Shi argues otherwise.

   It is well-established that jurisdiction over a defendant is
not impaired by the fact that he was brought within the juris-
dictional territory of the court against his will. See Frisbie v.
Collins, 

, 522 (1952); Ker v. Illinois, 

(1886).6 Yet Shi argues that § 2280 creates an exception
to this rule because it requires the defendant to be “later
found” in the United States. 18 U.S.C. § 2280(b)(1)(C).
Accordingly, he reads the statute to require a defendant to
enter the United States voluntarily before he can be prose-
cuted.

   The D.C. Circuit rejected an identical argument launched
against a similar statute. In Rezaq, a foreign defendant was
arrested abroad and tried in the United States for violating 49
U.S.C. app. § 1472(n) (1994), an anti-hijacking 

. Section 1472(n) requires the defendant to be
“afterwards found” in the United States and the defendant
argued that this language required that he enter the United
States voluntarily. The D.C. Circuit rejected this interpreta-
tion, holding that “the word ‘found’ means only that the
hijacker must be physically located in the United States, not
that he must be first detected here.” 

(emphasis added).7
  6
     Indeed, in certain circumstances, jurisdiction will satisfy due process
even when a foreign national is forcibly abducted in another country by
United States officials for the sole purpose of being brought to trial here.
See United States v. Alvarez-Machain, 

, 661-62 (1992).
   7
     In a similar case, the Second Circuit in Yousef upheld jurisdiction over
a foreign defendant under 18 U.S.C. § 32(b), which requires the defendant
to be “afterwards found” in the United 

. In that case,
the defendant was arrested in Pakistan and transferred to the United States
on charges relating to his role in the 1993 World Trade Center bombing.

Subsequent to his arrival, the government added charges
under § 32(b) for the unrelated bombing of a Philippine Airlines plane. 

argued that jurisdiction was improper under § 32(b)’s “af-
4384                      UNITED STATES v. SHI
   [10] We are persuaded by this analysis, and conclude that
the requirement that a defendant be “later found” does not
contain the implicit requirement that the defendant’s arrival in
the United States be voluntary. Indeed, if Congress intended
to create such an exception to the Ker-Frisbie rule, we would
expect it to manifest its intent more directly. Moreover, the
Maritime Safety Convention contains no such voluntary entry
requirement. See Maritime Safety Convention, art. 9. To the
extent Congress intended § 2280 to deviate from the Conven-
tion it was designed to implement, we would expect such an
instruction to be express.

   [11] Accordingly, we conclude that Shi’s arrest on the Full
Means No. 2 after the United States had established jurisdic-
tion over the ship and his subsequent transport to the Hono-
lulu federal building rendered him “later found” in the United
States and subjected him to jurisdiction under § 2280. With
the propriety of the district court’s jurisdiction now estab-
lished, we turn to Shi’s additional challenges to his convic-
tion.

                                    III

   Shi next argues that the indictment against him was insuffi-
cient. The indictment contained every element of

terwards found” provision because he did not enter the United States vol-
untarily. 

The Second Circuit disagreed, noting that “[b]y the time
Yousef was charged with the crime . . . he was already lawfully in federal
custody in the United States.” 

While the court’s reasoning sug-
gests that the voluntariness of the defendant’s arrival was irrelevant to
determining whether he was “afterwards found” in the United States, 

the court considered the fact that Yousef was not charged under
§ 32(b) until after he was inside the United States to be of some signifi-
cance, id.; see also United States v. Yunis, 

(D.C. Cir. 1991)
(holding that a foreign defendant was subject to jurisdiction under
§ 1472(n) even though he did not enter the United States voluntarily, but
noting the fact that the defendant was already inside U.S. territory before
he was charged).
                          UNITED STATES v. SHI                          4385
§§ 2280(a)(1)(A) and (B), the offenses with which Shi was
charged. As such, it fairly informed him of the charges against
him and “enable[d] him to plead an acquittal or conviction in
bar of future prosecutions for the same offense.” United States
v. Vroman, 

, 670-71 (9th Cir. 1992) (internal
quotation marks and citation omitted). Yet Shi contends that
the indictment was flawed because it failed to allege that he
engaged in acts of terrorism.8 Sections 2280(a)(1)(A) and (B)
contain no such requirement.

   [12] The face of the statute does not reference “terrorism”
or suggest that its scope is limited to terrorist acts. Moreover,
the statutory context does not indicate that such limitation
exists. Section 2280 is codified in Title 18, Part I, Chapter 111
of the U.S. Code, which describes offenses related to “Ship-
ping.” A separate Chapter defines offenses related to “Terror-
ism.” See Title 18, Part I, Chapter 113b. Shi correctly notes
that a violation of § 2280 is one of several offenses which
may constitute a “federal crime of terrorism,” but fails to note
that such classification requires additional statutory showings.
See 18 U.S.C. § 2332b(g)(5)(B)(i) (listing § 2280 as one
offense which may be prosecuted as a “federal crime of ter-
rorism” if such offense is “calculated to influence or affect the
conduct of government by intimidation or coercion, or to
retaliate against government conduct”). That a violation of
§ 2280 may be a “federal crime of terrorism” in certain cases
does not imply that “terrorism” is an element of the crime.
Accordingly, we conclude that the indictment against Shi was
sufficient.
  8
    We reject Shi’s separate argument that the indictment was insufficient
because it failed to allege that the deaths of the Captain and First Mate
occurred “in connection with” Shi’s acts. Sections 2280(a)(1)(A) and (B)
contain no such language. We also reject Shi’s argument that the indict-
ment was insufficient because it failed to allege the requisite state of mind.
Section 2280(a)(1) requires the defendant to act “unlawfully and intention-
ally.” All three counts of the indictment include this exact phrase.
4386                      UNITED STATES v. SHI
                                    IV

   We next turn to Shi’s argument that the district court erred
in admitting his March 21 confession to Agent Torikai into
evidence. Shi argues that such confession was inadmissible
because (1) it was tainted by his unwarned statements to Lt.
Fu on March 19 and 20; (2) Shi did not adequately waive his
Miranda rights upon his arrest; (3) Shi invoked his right to
silence, and (4) the confession was involuntary. We consider
each argument in turn.

                                     A

   Shi made statements to Lt. Fu on March 19 and 20 without
the benefit of Miranda warnings.9 The next day, after he
received the warnings, Shi confessed to Agent Torikai. The
Supreme Court has held that when a defendant’s properly-
warned confession is preceded by an unwarned statement or
statements, the confession may only be admitted if both the
pre-warning statements and the confession were voluntary, or
if the confession was sufficiently separated from the pre-
warning statement such that the “causal connection” between
the two statements would be “speculative and attenuated.”
Oregon v. Elstad, 

, 313-14 (1985); see Missouri
   9
     At the time of Shi’s statements to Lt. Fu, he remained a prisoner of the
crew. We have held that an officer’s obligation to administer Miranda
warnings attaches only where the suspect is in custody. United States v.
Crawford, 

, 1059 (9th Cir. 2004) (en banc) (citations omit-
ted). In asking this question, we examine the totality of the circumstances
from the perspective of a reasonable person in the suspect’s position. 

v. McCarty, 

, 442 (1984)). In this case, Shi
was unquestionably in custody, but he was in the custody of the crew of
the Full Means No. 2, not the United States. In such an unusual circum-
stance, it is not clear whether Miranda warnings are required. Because we
are only asked to decide whether Shi’s statements to Lt. Fu tainted his
later confession to Agent Torikai, we decline to resolve such question
here. Instead, we assume, without deciding, that Miranda warnings were
required.
                     UNITED STATES v. SHI                 4387
v. Seibert, 

, 619-20 (2004) (Kennedy, J., concur-
ring).

   Although the district court concluded that Shi’s statements
to Lt. Fu on March 19 and 20 were voluntary, it assumed for
purposes of this analysis that the statements were involuntary
because of the poor conditions of the storage compartment in
which Shi was confined at the time. We proceed on the same
assumption. As such, Shi’s confession to Agent Torikai is
admissible only if it was sufficiently attenuated from his
March 19 and 20 statements.

   In undertaking this analysis, we consider (1) the temporal
proximity between the statements; (2) the intervening circum-
stances; and (3) the purpose and flagrancy of the official mis-
conduct. United States v. Jenkins, 

, 941 (9th Cir.
1991) (citing Brown v. Illinois, 

, 603-04 (1975)).
Our examination of the degree of attenuation “is merely
another way of asking whether the subsequent confession
was, itself, voluntary.” 

case, one full day elapsed between Shi’s March 20
statement to Lt. Fu and his properly-warned confession. In
addition, several significant intervening events separated the
pre-warning statements from Shi’s properly warned confes-
sion. First, Shi’s unwarned statements were made to Coast
Guard Lt. Fu, while his properly-warned confession was made
to FBI Agent Torikai. Second, Shi’s unwarned statements
were made on board the Full Means No. 2, while his Miran-
dized confession was made at the Honolulu federal building.
Third, during the time that elapsed between Shi’s March 20
statement and his confession, Shi was fed, treated by a health
technician, given a change of clothes, and twice permitted
access to a restroom.

  [13] In addition to these intervening events, we note that
Shi’s unwarned statements were not the product of purposeful
or flagrant official misconduct. See 

spoke to Shi
4388                  UNITED STATES v. SHI
before the Coast Guard had exercised jurisdiction over the
Full Means No. 2 and testified that his purpose in engaging
Shi was not to ascertain his guilt, but to determine whether
Shi would corroborate the crew’s story or whether the crew
was simply staging the emergency. As the Supreme Court has
explained, “[i]t is an unwarranted extension of Miranda to
hold that a simple failure to administer the warnings, unac-
companied by any actual coercion or other circumstances cal-
culated to undermine the suspect’s ability to exercise his free
will, so taints the investigator’s process that a subsequent vol-
untary and informed waiver is ineffective for some indetermi-
nate period.” 

. Even if Lt. Fu’s
decision to speak with Shi without first reading the Miranda
warnings was imprudent, we cannot conclude that it was cal-
culated to overcome Shi’s exercise of his free will. Accord-
ingly, we conclude that whatever taint was caused by Shi’s
unwarned statements to Lt. Fu does not preclude the admis-
sion of Shi’s properly-warned confession to Agent Torikai.

                               B

   Even if the taint of his pre-warning statements was suffi-
ciently dissipated, Shi argues that his confession to Agent
Torikai must be excluded because he did not adequately
waive his Miranda rights. To admit an inculpatory statement
made by a defendant during custodial interrogation, the defen-
dant’s “waiver of Miranda rights must be voluntary, knowing,
and intelligent.” United States v. Garibay, 

, 536
(9th Cir. 1998) (internal quotation marks and citation omit-
ted). A valid waiver of Miranda rights depends upon the “to-
tality of the circumstances including the background,
experience, and conduct of defendant.” 

marks and citation omitted). The prosecution bears the burden
of proof, and there is a presumption against waiver. 

37 (internal quotation marks and citation omitted).

                               1

   “A waiver is voluntary if, under the totality of the circum-
stances, the confession is the product of a free and deliberate
                      UNITED STATES v. SHI                  4389
choice rather than coercion or improper inducement.” United
States v. Doe, 

, 1074 (9th Cir. 1998) (citation
omitted). Prior to his arrest, Shi spent four days in a storage
compartment where he had been kept by the crew. Still, the
district court found that upon his release from the compart-
ment, Shi appeared coherent and alert. Indeed, the district
court credited the agents’ description of Shi’s demeanor as
“cocky” and “not timid at all.” In addition, Shi was allowed
access to a bathroom before the agents escorted him to the
dining area to read him the warnings.

   Finally, there is no evidence of police coercion. See United
States v. Kelley, 

, 565 (1992) (“Coercive police
activity is ‘a necessary predicate’ to finding a confession
involuntary.”) (quoting Colorado v. Connelly, 

,
167 (1986)). While the conditions in the storage compartment
were quite troubling, Shi was in the compartment as the
crew’s prisoner, not the Coast Guard’s or the FBI’s. Once the
FBI released Shi from the compartment and assumed custody,
the district court found no evidence that the FBI intimidated
or coerced Shi in any way, or that there was “anything . . . that
would render the atmosphere combative.” We require “some
causal connection” between police conduct and the defen-
dant’s statement to render it involuntary. 

ted). No such connection exists here.

   [14] Accordingly, Shi’s coherent and “cocky” demeanor
and the absence of improper tactics by the agents satisfy us
that his waiver was the product of a free and deliberate
choice.

                               2

  Nevertheless, even if a waiver is voluntary, we must also
determine whether the district court’s finding that such waiver
was “knowing and intelligent” was clearly erroneous. United
States v. Rodriguez-Preciado, 

, 1127 (9th Cir.
2005) (internal quotation marks and citation omitted). The
4390                  UNITED STATES v. SHI
language barrier between Shi and the agents is relevant, see

, and the district court took account
of such fact in making its determination. First, it credited Lan-
guage Specialist Wun’s testimony that he maintained a “90 to
95%” level of understanding with Shi throughout their
exchange. Second, the district court noted that the Advice of
Rights form provided to Shi was written in Mandarin.
Although Mandarin was not Shi’s native dialect, Shi had a
ninth grade education and, when asked by Language Special-
ist Wun, stated that he understood the form. Finally, the dis-
trict court found Shi’s dismissal of Agent Torikai’s questions
as “insignificant” to be a product of his “cockiness” rather
than confusion, and that Torikai and Wun’s rearticulation of
the Miranda rights eliminated whatever confusion did exist.

   Based on this record, we conclude that the district court did
not clearly err in concluding that Shi’s waiver was knowing
and intelligent. See 

(quoting Moran v.
Burbine, 

, 421 (1986)); 

(concluding that a district court did not com-
mit clear error in finding that a foreign defendant made a
valid waiver despite confusion between the interrogating offi-
cers and the defendant over the word “methamphetamine”
because the defendant told the officers he understood his
rights and the officers did not indicate that the defendant had
difficulty understanding English).

                               C

   Even if Shi’s initial waiver were valid, he contends that he
invoked his right to silence before he spoke. “Once a person
invokes the right to remain silent, all questioning must cease.”
Anderson v. Terhune, 

, 784 (9th Cir. 2008) (en
banc) (citing Miranda v. Arizona, 

, 473-74
(1966)). While a defendant who invokes his right to counsel
must do so unambiguously, Davis v. United States, 

, 459 (1994), we have not yet determined whether such
rule applies when a defendant invokes his right to silence.
                     UNITED STATES v. SHI                  4391
Still, we have established that, at a minimum, such invocation
must not be “so equivocal or unclear that ‘a reasonable officer
in light of the circumstances would have understood only that
the suspect might be invoking’ his right to remain silent.”
Arnold v. Runnels, 

, 866 (9th Cir. 2004) (quoting

(emphasis in original)).

   Shi suggests that his dismissal of Agent Torikai’s questions
as “insignificant” was an invocation of his right to silence.
But as the district court explained, such claim is belied by the
fact that Shi consistently manifested his willingness to answer
questions and that Shi signed the waiver form after making
this comment.

   [15] These facts distinguish this case from United States v.
Heldt, 

(9th Cir. 1984), the principal authority
on which Shi relies. In Heldt, the defendant was read his
Miranda rights and provided with a waiver form, but told his
interrogator that he “understood his rights, but did not wish to
waive them, and that he . . . did not wish to answer questions.”

(emphasis added). We concluded that Heldt’s
refusal to sign the form was important evidence supporting
the finding that he did not waive his rights. 

-78.
Yet as we later explained in United States v. Andaverde, 

(1995), a defendant’s refusal to sign the waiver
form alone does not render his waiver invalid. 

(citations omitted). Rather, “a refusal to sign a waiver form is
an ‘indication’ that the defendant is invoking his right to
silence which casts ‘initial doubt’ on the government’s waiver
claim.” 

(quoting 

) (empha-
sis added). Additional evidence is necessary to confirm that
initial doubt. For example, in Heldt, “the defendant verbally
refused to answer questions and was ‘exhorted’ to answer by
police.” Id. (quoting 

-78) (emphasis
added). Here, Shi never refused to sign the form or to answer
questions, merely referring to Torikai’s questions as “insignif-
icant.” Once Torikai again explained the rights, Shi signed the
form.
4392                 UNITED STATES v. SHI
   Shi also argues that he invoked his right to silence during
his interrogation at the federal building when he said to Agent
Torikai “I don’t want to talk about the accident.” But as the
district court explained, once Torikai responded by reminding
Shi of the waiver form the fact that Shi had the right to stop
talking at any time, Shi continued to respond to questions.

   We conclude that Shi’s comment would not have caused a
reasonable officer in the circumstances to understand any-
thing more than that Shi “might” have been invoking his right
to remain silent. See 

. Accordingly,
Agent Torikai was not required to terminate the interrogation.

                              D

   Finally, we consider Shi’s claim that his confession was
involuntary. “A confession is involuntary if coerced either by
physical intimidation or psychological pressure.” United
States v. Haswood, 

, 1027 (9th Cir. 2003) (cita-
tion omitted). We consider the totality of the circumstances in
engaging in this inquiry. United States v. Gamez, 

, 1144 (9th Cir. 2002) (citing Dickerson v. United States,

, 434 (2000)). Relevant factors include: (1) the
time between the defendant’s arrest and arraignment, (2)
whether the defendant knew the nature of the offense with
which he was charged at the time of his confession, (3)
whether the defendant was aware that he was not required to
make any statement, (4) whether the defendant had been
advised of his right to counsel, and (5) whether counsel was
present at the time of the defendant’s confession. 

U.S.C. § 3501(b)).

   [16] The time that elapsed between Shi’s arrest and his
arraignment (approximately 19 hours) was reasonably limited.
See 

31-hour delay reasonable where the defen-
dant did not speak English, could not be interrogated until an
interpreter arrived, and was arraigned at the first available
opportunity after interrogation was complete). Moreover, the
                     UNITED STATES v. SHI                  4393
agents informed Shi of the charges against him upon his
arrest. In addition, Agent Torikai informed Shi of his right to
counsel and his right to remain silent. See 

(finding foreign national’s confession to be voluntary where
he was interrogated and advised of his rights in his native lan-
guage, even though he was not assisted by counsel). Of
course, in the case of a foreign national, we consider whether
extra steps were taken to ensure that the defendant understood
his rights. United States v. Amano, 

, 804-05 (9th
Cir. 2000). In this case, Shi was read his rights by an inter-
preter who maintained a “90 to 95 percent” level of under-
standing with him and Shi signed a Miranda waiver written
in Mandarin Chinese. Shi told the agents he understood the
form. Although this was Shi’s first interaction with the United
States criminal justice system, we agree with the district court
that these facts indicate that Shi’s statement was voluntary.
See 

(holding that a defendant’s inexperience with
the United States criminal justice system and his lack of con-
tact with the consulate did not render his Miranda waiver
involuntary).

                               E

  [17] Based on the foregoing, the district court properly
admitted into evidence Shi’s March 21 confession to Agent
Torikai at the federal building.

                               V

  We now move to Shi’s argument that the district court
should have suppressed the writings seized from his bunk area
because the search warrant was deficient and because the
scope of the FBI agents’ search was overbroad.

                               A

   The affidavit accompanying the search warrant listed
§ 2280 as the offense charged, but the warrant itself did not
4394                      UNITED STATES v. SHI
cite § 2280 or describe the acts it prohibits. Shi argues that
this rendered the warrant deficient because it failed to notify
the executing agents as to what evidence would be relevant to
a prosecution under this uncommon statute.

   [18] We need not determine whether the warrant’s failure
to refer to § 2280 created a technical deficiency under the
Fourth Amendment if we conclude that the executing agents
relied on the warrant in good faith. United States v. Crews,

, 1135-36 (9th Cir. 2007). Good faith reliance
exists if the agents’ affidavit establishes “at least a colorable
argument for probable cause,” and the agents relied on the
search warrant in an objectively reasonable manner. United
States v. Luong, 

, 903 (9th Cir. 2006). The dis-
trict court found that whatever the consequence of the war-
rant’s failure to cite § 2280, the agents were entitled to the
good faith exception because the affidavit they filed listed the
statute and because the same agents who executed the warrant
prepared the affidavit. We agree.

   [19] The affidavit, which is incorporated by reference into
the warrant, cites § 2280 and explains that Shi stabbed the
Captain and First Mate and took control of the ship. Thus,
even if § 2280 is an uncommon statute, we are satisfied that
the affidavit adequately notified the executing agents of the
evidence relevant to the charged crimes. Moreover, none of
the factors which preclude the application of the good faith
exception apply here.10 Accordingly, we conclude that even if
the warrant was technically deficient, the executing agents
were entitled to the good faith exception.
   10
      Specifically, (1) the agents did not mislead the magistrate judge with
false statements or reckless disregard for the truth; (2) Shi does not allege
that the magistrate judge abandoned her neutral role in reviewing the war-
rant application; (3) the warrant describes the place to be searched and the
things to be found in adequate detail; and (4) the affidavit is not so lacking
in indicia of probable cause that no reasonable officer could rely upon it
in good faith. See United States v. Leon, 

, 923-26 (1984).
                     UNITED STATES v. SHI                   4395
   We also reject Shi’s argument that the warrant was defi-
cient because it did not describe the items to be seized with
sufficient particularity. The search warrant authorized the FBI
agents to seize, among other things:

    items of personal property which tend to identify the
    person(s) in control, possession, and ownership of
    the property that is the subject of this warrant,
    including, but not limited to mail, photographs, per-
    sonal telephone books, diaries, journals, bills and
    statements, keys, identification cards and documents,
    passport and related travel documents, bank books,
    checks, and check registers.

The warrant authorized a search only of the “[b]unk space,
cupboard, drawer, and two storage spaces” which the crew
had told the agents belonged to Shi.

   The Fourth Amendment prohibits “general warrants” and
prevents law enforcement from engaging in general explor-
atory searches. United States v. Adjani, 

, 1147-
48 (9th Cir. 2006) (citations omitted). However, “ ‘[w]arrants
which describe generic categories of items are not necessarily
invalid if a more precise description of the items subject to
seizure is not possible.’ ” 

States v. Spi-
lotro, 

, 963 (9th Cir. 1986)). When determining
whether a warrant which authorizes the seizure of a category
of items is overbroad, we consider: (1) whether probable
cause existed to seize all items of a category described in the
warrant; (2) whether the warrant set forth objective standards
by which executing officers could differentiate items subject
to seizure from those which were not; and (3) whether the
government could have described the items more particularly
in light of the information available to it at the time the war-
rant issued. United States v. Noushfar, 

, 1447
(9th Cir. 1996) (citing 

).

  [20] In this case, there was probable cause to seize items of
Shi’s property which could identify him as the person in con-
4396                  UNITED STATES v. SHI
trol of the bunk area, including his mail. Further, the warrant
only authorized the agents to seize written documents from
the prescribed area that could identify Shi. Under such limita-
tion, written materials such as books, magazines, or newspa-
pers containing no identifying information would not be
subject to seizure. Finally, the agents lacked additional infor-
mation which would have allowed a more specific description
of the items to be seized. See 

conclude
that the warrant adequately described the items to be seized.
Compare United States v. Holzman, 

, 1509 (9th
Cir. 1989) (upholding warrant authorizing a search for “any
cash, jewelry, bonds and notes obtained through this fraud
scheme”); with United States v. Kow, 

, 425-26
(9th Cir. 1995) (holding a warrant to be insufficiently particu-
larized where it authorized officers to seize from a video store
any documents fitting under one of several dozen general cat-
egories).

                               B

   Finally, Shi argues that the search of his bunk space was
overbroad because the agents seized written materials written
in Chinese without sending an agent fluent in Chinese to the
scene who could assess the relevance of such documents.
“The general touchstone of reasonableness which governs
Fourth Amendment analysis . . . governs the method of execu-
tion of the warrant.” United States v. Ramirez, 

,
71 (1998) (citation omitted). In this case, the warrant autho-
rized the agents to search for items of personal property which
could identify Shi, including mail, photographs, diaries, and
passports, among other things. Although the agents expected
such documents to be written in Chinese, it does not require
a person fluent in Chinese to identify documents which meet
this definition, even if such person is unable to interpret their
contents. For example, even a person who cannot read a for-
eign language will likely be able to distinguish documents in
a foreign language capable of identifying their owner (e.g.,
personal mail) from those which are not (e.g., magazines or
                          UNITED STATES v. SHI                         4397
newspapers). As the Third Circuit has explained, “there are
plainly circumstances in which it is reasonable to execute a
warrant for documents in a foreign language (or for technical
records) without the assistance of an officer who is capable of
understanding the materials sought.” United States v. Ninety-
Two Thousand Four Hundred Twenty-Two Dollars and Fifty-
Seven Cents, 

, 153 (3d Cir. 2002) (Alito, J.).

   [21] We are persuaded that this is such a case; we conclude
that the agents did not act unreasonably in failing to enlist the
help of an agent fluent in Chinese in conducting the search.

                                    VI

   Our final task is to consider whether the sentence imposed
by the district court was reasonable. This requires us first to
determine whether the district court committed a “significant
procedural error.” United States v. Carty, 

,
*5 (9th Cir. 2008) (en banc) (“It would be procedural error for
a district court to fail to calculate—or to calculate incorrectly
—the Guidelines range; to treat the Guidelines as mandatory
instead of advisory; to fail to consider the § 3553(a) factors;
to choose a sentence based on clearly erroneous facts; or to
fail adequately to explain the sentence selected, including any
deviation from the Guidelines range.” (citing Gall v. United
States, 

, 597 (2007))). If the district court’s sen-
tence is free from procedural error, we next consider the “sub-
stantive reasonableness of the sentence.” 

128
S. Ct. at 597).

   [22] The district court correctly determined that the appli-
cable Sentencing Guideline for Shi’s case was U.S.S.G.
§ 2A1.1, which provides the advisory sentencing range for
certain felonies resulting in death, including § 2280.11
  11
    Shi contends that the application of this Guideline required the district
court to find facts not proven to a jury because § 2A1.1 requires the
offender to have committed a “premeditated killing,” yet the indictment
4398                     UNITED STATES v. SHI
Although that Guideline recommends a maximum sentence of
life imprisonment, the district court departed downward and
sentenced Shi to 36 years.

   [23] Title 18 U.S.C. § 3553(a) lists the factors to be consid-
ered by a district court imposing a sentence.12 The district
court considered each factor in applying its downward depar-
ture. The court noted Shi’s personal history, which was free
from prior criminal activity, the unique circumstances of his
crime, and the fact that no victims had claimed restitution. It
also noted that Shi’s acts were violent, serious, and put the
lives of the crew at risk.13 In light of the district court’s careful
consideration of the § 3553(a) factors, we are satisfied that the
sentence it imposed was not unreasonable. See 

; Rita v. United States, 

, 2468-
69 (2007).

                                   VII

   For the foregoing reasons, Shi’s conviction and sentence

never included such an allegation. This argument is without merit. While
§ 2A1.1 does apply to “cases of premeditated killing,” it “also applies
when death results from the commission of certain felonies,” including
§ 2280. U.S.S.G. § 2A1.1(a)(1) app. n.1 (emphasis added).
   12
      These factors include: (1) the nature and circumstances of the offense
and the history and characteristics of the defendant; (2) the need for the
sentence imposed; (3) the kinds of sentences available; (4) the kinds of
sentences and the sentencing range established by the Sentencing Guide-
lines; (5) pertinent policy statements issued by the Sentencing Commis-
sion; (6) the need to avoid unwarranted sentencing disparities among
defendants who have similar criminal records and have been found guilty
of similar conduct; and (7) the need to provide restitution to victims. 18
U.S.C. § 3553(a).
   13
      In a case of a felony resulting in death, § 2A1.1 advises a downward
departure only “if the defendant did not cause the death intentionally or
knowingly.” U.S.S.G. § 2A1.1(a)(1) app. n.2(B).
              UNITED STATES v. SHI   4399
imposed are

  AFFIRMED.