                 FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                 No. 04-50519
                Plaintiff-Appellee,
               v.                           D.C. No.
                                          CR-03-02234-IEG
ROBERTO LEAL-CRUZ,
                                             OPINION
             Defendant-Appellant.
                                      
       Appeal from the United States District Court
          for the Southern District of California
     Irma E. Gonzalez, Chief District Judge, Presiding

                 Argued and Submitted
        September 15, 2005—Pasadena, California

                  Filed December 9, 2005

      Before: J. Clifford Wallace, Barry G. Silverman,
        and Consuelo M. Callahan, Circuit Judges.

                Opinion by Judge Callahan




                           16133
                 UNITED STATES v. LEAL-CRUZ              16135


                         COUNSEL

Roseline D. Feral, San Diego, California, for the defendant-
appellant.

Assistant United States Attorney David P. Curnow, San
Diego, California, filed the brief, and Assistant United States
Attorney Kevin Mulcahy, San Diego, California, argued the
cause for the plaintiff-appellee.


                         OPINION

CALLAHAN, Circuit Judge:

   Roberto Leal-Cruz appeals his conviction for attempted
illegal reentry into the United States after deportation, under
16136            UNITED STATES v. LEAL-CRUZ
8 U.S.C. § 1326. Leal-Cruz contends that the district court
erred by instructing the jury that he had the burden of proving
his duress defense. We have jurisdiction to review appellant’s
conviction pursuant to 28 U.S.C. § 1291 and we affirm.

                               I

   Roberto Leal-Cruz, a citizen of Mexico, attempted to reen-
ter the United States on July 12, 2003. Around 1:00 a.m., he
was observed by United States border patrol agents in Calex-
ico, California, climbing over the 15 to 20 foot international
boundary fence separating the United States from Mexico. A
border patrol agent chased Leal-Cruz for two blocks in the
United States before he surrendered.

   Leal-Cruz testified that about two weeks earlier, Mexican
police officers beat him up and left him for dead. The same
police officers spotted him on the date of his attempted reen-
try, when he was pumping gas on the Mexican side of the bor-
der. When he saw the police officers, Leal-Cruz ran
approximately three blocks to the international boundary
fence. After jumping the fence and seeing United States bor-
der patrol officers, he retreated back up the fence and sat on
top of it, not wanting to be captured inside of the United
States. The Mexican police appeared at that time and, because
he feared for his life, Leal-Cruz jumped to the American side
of the fence and ran, hoping to avoid being apprehended by
the United States agents. After a brief foot chase, he surren-
dered.

   The district court concluded that although the evidence
presented at trial warranted a duress instruction, the act of
crossing the international boundary fence into the United
States did not negate the specific intent element of attempted
illegal reentry and therefore could only be offered to excuse
Leal-Cruz’s criminal conduct. The district court instructed the
jury with Ninth Circuit Model Criminal Jury Instruction 6.6,
                      UNITED STATES v. LEAL-CRUZ                     16137
which placed the burden on Leal-Cruz to prove duress by a
preponderance of the evidence.1

                                     II

   [1] As a preliminary matter, we must decide whether Leal-
Cruz waived his right to challenge the jury instruction under
the invited error doctrine. United States v. Perez, 116 F.3d
840, 845 (9th Cir. 1997) (en banc), holds that an error is
waived and unreviewable when a defendant both invites the
error and affirmatively relinquishes or abandons a known
right. A challenge to a jury instruction is waived under the
invited error doctrine when, in spite of being aware of the
applicable law, the defendant accepts a flawed instruction. Id.
Perez requires that counsel’s conduct rise to the level of an
affirmative relinquishment of the right to challenge the
instruction on appeal. Id. We hold here that the instruction is
reviewable because Leal-Cruz did not affirmatively abandon
or relinquish his challenge to the instruction.

   [2] At the final jury instruction conference, defense counsel
asked that the instruction be supplemented to explain that if
the defendant established duress by a preponderance of the
  1
   The given instruction read:
      The defendant must prove duress by a preponderance of the evi-
      dence. A preponderance of the evidence means that you must be
      persuaded that the things the defendant seeks to prove are more
      probably true than not true. A defendant acts under duress only
      if at the time of the crime charged:
      1. there was an immediate threat of death or serious bodily injury
      to the defendant if the defendant did not commit the crime;
      2. the defendant had a well-grounded fear that the threat of death
      or serious bodily injury would be carried out; and
      3. the defendant had no reasonable opportunity to escape the
      threatened harm.
      If you find that each of these things has been proved by a prepon-
      derance of the evidence, your verdict should be for the defendant.
16138            UNITED STATES v. LEAL-CRUZ
evidence, then the burden shifted to the government to dis-
prove duress beyond a reasonable doubt. Counsel specifically
requested that language from Model Instruction 6.5 (requiring
the prosecution to prove absence of duress) be included in the
given instruction. Although defense counsel did not formally
object when the judge disagreed with her request to supple-
ment Model Instruction 6.6 with language from Model
Instruction 6.5, counsel nevertheless disagreed with what the
court concluded was the applicable law. Despite counsel’s
failure to articulate clearly her position at the final jury
instruction conference, we conclude that her failure to object
formally to the given instruction does not rise to the level of
an affirmative relinquishment or abandonment of Leal-Cruz’s
right to challenge the instruction on appeal. Therefore, Leal-
Cruz did not waive his challenge to the jury instruction under
the invited error doctrine.

                              III

  Whether Leal-Cruz has the burden of proving his duress
defense is a question of law, and is therefore reviewed de
novo. United States v. Martinez-Martinez, 369 F.3d 1076,
1083 (9th Cir. 2004); United States v. Meraz-Solomon, 3 F.3d
298, 299 (9th Cir. 1993) (per curiam).

   [3] In In re Winship, the Supreme Court held that “the Due
Process Clause protects the accused against conviction except
upon proof beyond a reasonable doubt of every fact necessary
to constitute the crime with which he is charged.” 397 U.S.
358, 364 (1970). Since that case, the Court has struggled with
the proper extent to which legislatures may define the ele-
ments of crimes and shift the burden of proof to the defen-
dant. The cases that follow establish two core principles:
Legislatures retain broad leeway in defining elements of
crimes and the requisite mens rea. However, once a govern-
ment has established the applicable elements it must prove
each of them beyond a reasonable doubt and may not lessen
its responsibility by shifting the burden of persuasion to the
                  UNITED STATES v. LEAL-CRUZ              16139
defendant on any issue which negates an element the govern-
ment is required to prove.

   In the first major post-Winship burden shifting case, the
Court held that Maine had impermissibly lessened its burden
of proof by shifting the burden to the defendant to prove “heat
of passion” in order to reduce murder to manslaughter. Mul-
laney v. Wilbur, 421 U.S. 684, 697-01 (1975). Maine had
retained the common law definition of murder whereby “mal-
ice aforethought is an essential and indispensable element of
the crime of murder.” Id. at 686. There, the Maine Supreme
Judicial Court had held that “malice aforethought and heat of
passion on sudden provocation are two inconsistent things.”
Id. at 686-87. Thus, the Court stated that “by proving the lat-
ter the defendant would negate the former and reduce the
homicide from murder to manslaughter.” Id. at 687. The
Court held that by requiring the defendant to negate an ele-
ment on which the state had the burden of proof, Maine had
impermissibly lessened its burden under Winship and there-
fore reversed Mullaney’s conviction. Id. at 700-01.

   Shortly after Mullaney, the Court reached the opposite
result in Patterson v. New York, 432 U.S. 197 (1977). New
York had created a defense of “extreme emotional distur-
bance” which would reduce murder to manslaughter and
shifted the burden of proof to the defendant on that defense.
Id. at 198-99. Unlike Maine, however, New York also had
adopted a differing definition of murder which had two ele-
ments: (1) intent to cause the death of another person and (2)
causing the death of such person or of a third person. Id. at
198 (quotations, punctuation, and citation omitted). The Court
distinguished Mullaney because while in that case “malice,
i.e., lack of provocation, was presumed and could be rebutted
by the defendant only by proving by a preponderance of evi-
dence that he acted with heat of passion upon sudden provo-
cation,” under New York law “nothing was presumed or
implied against Patterson.” Id. at 216. The key distinction thus
appears to be that proof of “extreme emotional disturbance”
16140            UNITED STATES v. LEAL-CRUZ
did not disprove or negate the required intent—the “intent to
cause the death of another person.” New York was therefore
free to create a mitigation defense and place the burden on the
defendant to prove the defense by a preponderance of the evi-
dence. The Court concluded that “[t]he Due Process Clause
. . . does not put New York to the choice of abandoning those
defenses [which place the burden on the defendant] or under-
taking to disprove their existence in order to convict of a
crime which otherwise is within its constitutional powers to
sanction by substantial punishment.” Id. at 207-08.

   The Court later upheld shifting the burden of persuasion on
self-defense in Martin v. Ohio, 480 U.S. 228 (1987). In that
case, the Court again appeared to endorse the same “negate
the required elements test” when it stated “[w]e are thus not
moved by assertions that the elements of aggravated murder
and self defense overlap in the sense that evidence to prove
the latter will often tend to negate the former.” Id. at 234.

  These principles have been reaffirmed by the Supreme
Court. Most recently, in Apprendi v. New Jersey, the Court
suggested a similar “negation” test with its discussion of Mul-
laney and Patterson when it stated that “New York, unlike
Maine, had not made malice aforethought, or any described
mens rea, part of its statutory definition of second-degree
murder . . . .” 530 U.S. 466, 485 n.12 (2000).

   [4] From these cases we conclude that the Due Process
Clause forbids shifting the burden of proof to the defendant
on an issue only where establishing the defense would neces-
sarily negate an element that the prosecution must prove
beyond a reasonable doubt under Winship. We are also mind-
ful that legislatures must be given flexibility in defining the
operative elements of a crime and the requisite mens rea for
each element. With this framework in mind, we turn to the
applicable Ninth Circuit precedents that are relevant to this
appeal.
                  UNITED STATES v. LEAL-CRUZ               16141
   [5] Our own precedents have held that when a defense
negates the element of a crime, it is unconstitutional to place
the burden of proving the defense on the defendant. United
States v. Hernandez-Franco, 189 F.3d 1151, 1157 (9th Cir.
1999) (citing Walker v. Endell, 850 F.2d 470, 472 (9th Cir.
1987)). The defense of duress, however, does not necessarily
negate the intent required to commit a specific intent offense.
Id. at 1158 (citing United States v. Fei Lin, 139 F.3d 1303,
1307 (9th Cir. 1998)). Attempted illegal reentry is a specific
intent crime. United States v. Gracidas-Ulibarry, 231 F.3d
1188, 1196 (9th Cir. 2000) (en banc) (defining the mens rea
element of attempted illegal reentry as “[having] the purpose,
i.e., conscious desire, to reenter the United States without the
express consent of the Attorney General”). Accordingly, we
must decide whether the duress asserted by Leal-Cruz negated
the specific intent element of attempted illegal reentry, the
position advanced by Leal-Cruz, or whether it could only be
offered to excuse his criminal conduct. Guided by circuit pre-
cedent, we hold that Leal-Cruz’s duress defense could only be
offered to excuse the offense.

   In Fei Lin, we determined that duress does not negate the
mens rea element of hostage taking or making ransom
demands. In so doing, we relied on Walker v. Endell, 850 F.2d
470 (9th Cir. 1987), which explained that duress does not
negate the specific intent element of kidnapping because “a
defendant can restrain another with the intent to inflict injury,
in the sense that he knows that his actions will lead to injury
or that his purpose is to cause injury, but act in this manner
in order to comply with the demands of another.” Id. at 473.
Applying this line of reasoning, we held that duress no more
negated the element of intent in Fei Lin than the specific
intent element of kidnapping in Walker. Fei Lin, 139 F.3d
1308.

  Later, in Hernandez-Franco, we held that a duress defense
did not negate the specific intent elements of attempt to trans-
port illegal aliens into the United States. 189 F.3d at 1158.
16142             UNITED STATES v. LEAL-CRUZ
Hernandez-Franco’s defense was that he was forced at gun-
point to drive the truck in which aliens were found. Adopting
the Fei Lin reasoning, the court concluded that “[a]ppellant
could intend to drive a truck with undocumented aliens to fur-
ther their illegal presence in the United States, but act in that
manner because someone had a gun to his head.” Id.

   Leal-Cruz attempts to distinguish Hernandez-Franco, argu-
ing that the intent element is greater for attempted illegal
reentry than for attempted transportation of illegal aliens, and
so, although duress may not negate the mens rea required for
attempted transportation of illegal aliens, it does negate the
mens rea element of attempted illegal reentry. We are not per-
suaded. As recognized in Hernandez-Franco, the attempt to
transport illegal aliens is a specific intent crime because (1) it
is an attempt crime, and (2) the statute requires a showing of
specific intent to further the alien’s illegal presence in the
United States. 189 F.3d at 1158. Even though we have
defined the specific intent element of attempted illegal reentry
as having the “purpose” or “conscious desire” to reenter the
United States unlawfully, we do not view this language as
establishing a mens rea different from the specific intent
required for attempted transportation of illegal aliens.

   Most recently, in United States v. Solorzano-Rivera, 368
F.3d 1073, 1080-81 (9th Cir. 2004), we decided that duress
did not negate the voluntariness of illegal reentry into the
United States—a general intent offense. Like Leal-Cruz,
Solorzano-Rivera presented a duress defense based on the
need to flee from abusive Mexican police officers. Id. at 1076.
Solorzano-Rivera argued that the burden was on the govern-
ment to prove absence of duress because his duress negated
the voluntariness of his act. Id. at 1080. This court disagreed,
concluding that his entry into the United States was voluntary
and his defense therefore could not be offered to negate an
element of the offense, but rather only to excuse the criminal
conduct. Id. at 1081.
                  UNITED STATES v. LEAL-CRUZ              16143
   The Solorzano-Rivera court provided examples of involun-
tary entries into the United States: An individual extradited to
the United States against his will, or paroled into the country
by proper authorities; or one who is sleeping on a train that
unexpectedly enters the country, or traveling on a plane that
makes an emergency landing in the country. Id. at 1080 (cit-
ing United States v. Quintana-Torres, 235 F.3d 1197, 1200
(9th Cir. 2000)). The court distinguished Solorzano-Rivera’s
conduct from the volitional conduct described in these exam-
ples, and concluded that jumping the international boundary
fence to escape Mexican police officers was a voluntary act.
Id. at 1080-81.

   [6] For the same reason that Solorzano-Rivera’s conduct
was voluntary, and the conduct of Hernandez-Franco, Fei Lin
and Walker was intentional, Leal-Cruz’s conduct was pur-
poseful. Leal-Cruz intended to enter the United States without
the express consent of the Attorney General. He had the “con-
scious desire” to enter the country, even if the act of crossing
the border was done to escape harm. Therefore, Leal-Cruz
had the burden of proving his duress defense, instead of the
government being required to prove absence of duress.

   Our holding makes particular sense when we consider that
the difference between a reentry into the United States and an
attempted reentry into the United States—when an alien is
apprehended in this country after jumping the international
boundary fence—is whether the alien is free from official
restraint. See United States v. Pacheco-Medina, 212 F.3d
1162 (9th Cir. 2000) (reversing a conviction for illegal reentry
into the United States because after jumping the international
boundary fence, the defendant was under constant and close
surveillance by United States agents). It would not make
sense to shift the burden of proving duress to the government
merely because Leal-Cruz was never free from official
restraint.
16144             UNITED STATES v. LEAL-CRUZ
                              IV

   [7] We conclude that Leal-Cruz’s reason for jumping the
international boundary fence did not negate the specific intent
element of attempted illegal reentry but rather could only be
offered as a legal excuse for committing the offense. Accord-
ingly, the district court properly instructed the jury and Leal-
Cruz’s conviction is AFFIRMED.
