                                    PRECEDENTIAL

  UNITED STATES COURT OF APPEALS
       FOR THE THIRD CIRCUIT
            _____________

                 No. 11-2875
                _____________

      UNITED STATES OF AMERICA

                       v.

              AARON TAYLOR,
                  Appellant
               _____________

  Appeal from the United States District Court
    for the Eastern District of Pennsylvania
    (D.C. Criminal No. 2-07-cr-00288-001)
  District Judge: Honorable Paul S. Diamond
                _____________

             Argued May 22, 2012

Before: RENDELL, FUENTES and HARDIMAN,
              Circuit Judges

        (Opinion Filed : July 25, 2012 )
                _____________
Mark E. Cedrone, Esq. [ARGUED]
Law Offices of Mark E. Cedrone
123 South Broad Street, Suite 810
Philadelphia, PA 19109
  Counsel for Appellant

Virgil B. Walker, Esq. [ARGUED]
Office of United States Attorney
615 Chestnut Street, Suite 1250
Philadelphia, PA 19106
  Counsel for Appellee
                       _____________

                OPINION OF THE COURT
                    _____________

RENDELL, Circuit Judge.

       This case requires us to consider whether, by including
“without just cause or excuse” in the federal assault with a
dangerous weapon statute, 18 U.S.C. § 113(a)(3), Congress
intended to convert justification, ordinarily a common-law
defense, into an element of the offense as to which the
government bears the burden of proof beyond a reasonable
doubt. Applying relevant Supreme Court precedent, we
conclude that the existence of just cause or excuse is an
affirmative defense to a § 113(a)(3) violation, and the
defendant bears the burden of proving it by a preponderance
of the evidence. Taylor also raises two issues relating to his
testimony and offers of proof regarding justification for the
assault and complains that he was selectively prosecuted. We
conclude, however, that none of those arguments has merit.
We will affirm the judgment of the District Court.




                              2
                               I.

                      A. Factual Background

      In the fall of 2006, defendant Aaron Taylor, who had
been convicted of drug and weapons charges, was an inmate
at the Federal Detention Center (FDC) in Philadelphia.
Because of some prior disciplinary violations, including
previous prison assaults, Taylor was assigned to the Special
Housing Unit (SHU), separate from the general prison
population.

        Prisoners in the SHU are allowed one hour of
recreation a day, five days a week, in a fifteen-by-fifteen foot
yard. Before each session, a guard asks every inmate whether
he would like to take or decline recreation. Two guards then
handcuff each inmate who desires recreation and transport
him to one of five enclosed yards. After the inmate enters the
yard, he turns his back to the locked door and places his
cuffed hands into a slot (also called a “wicket”) so the guards
on the other side of the door can uncuff him. The same
process occurs at the end of the hour: one at a time, the
inmates back up to the wicket so the guards can handcuff
them. Once all of the inmates have been handcuffed, the
guards unlock the door and transport the inmates back to their
cells. According to a prison guard who testified at Taylor‟s
trial, an inmate may decline recreation, and be returned to his
cell, at any time during the hour.

      According to Taylor, racial tensions at the FDC were
inflamed in September 2006 when a white, female
psychiatrist told Taylor, who is black, to stop looking at her.
Wayne Maruzin, a white inmate, overheard the exchange and,
according to Taylor, later discussed the incident with Peter




                               3
Bistrian, another white inmate. Bistrian then threatened
Taylor. About a week later, Taylor filed a complaint with the
warden asserting that the psychiatrist‟s comments were
racially motivated and exacerbated racial tension among the
inmates.

       In early October 2006, a guard mistakenly gave Taylor
an extra razor blade. Taylor used the extra blade to fashion a
knife, or “shank.”

       Then, on October 12, 2006, Taylor was placed in the
same recreation yard with Bistrian. The guards removed
Taylor‟s handcuffs before they removed Bistrian‟s, and the
two paced the yard for almost the entire hour. Taylor testified
that Bistrian did not make any aggressive move towards him
during the hour, but, after half an hour, Bistrian asked him
what he was looking at and, later, told him he was “going
down,” which Taylor understood to mean that Bistrian was
“going to come after” him.

       At the end of the hour, Bistrian backed up to the
wicket to be handcuffed. Taylor, who had not yet been
handcuffed, followed Bistrian, and, as soon as Bistrian was
handcuffed, attacked him. Taylor punched Bistrian and
slashed his face, arms, and legs with the shank. Bistrian fell
to the ground and kicked at Taylor. Taylor ignored the
guards‟ repeated commands to stop and continued attacking
Bistrian for more than two-and-a-half minutes. The guards
used three cans of pepper spray to try to subdue Taylor but
did not succeed until they tossed a “flash bang” grenade into
the yard, stunning him. When the guards entered the yard,
Taylor told them repeatedly that he “had to get” Bistrian
before Bistrian got him. Bistrian was treated at the hospital




                              4
for deep cuts to his face, arms, and legs. The entire incident
was captured on video by the FDC‟s surveillance cameras.

                      B. Procedural History

        Taylor was indicted and charged with assault with a
dangerous weapon, under 18 U.S.C. § 113(a)(3), and assault
resulting in serious bodily injury, under 18 U.S.C.
§ 113(a)(6), in May 2007. The government ultimately sought
dismissal of the second count, and the case went to trial on a
single count of assault with a dangerous weapon on
November 30, 2010. Taylor did not dispute that he had
attacked Bistrian, but attempted to show that he was justified
in doing so. Taylor was convicted on December 3, 2010, and,
on June 28, 2011, was sentenced to 120 months in prison, to
be served consecutively to the federal sentence he was
serving when the assault occurred.

        Before trial, Taylor moved to dismiss the indictment
for selective prosecution. His theory was that the prosecution
was racially motivated because he was charged for this
assault, on a white victim, but had not been charged for an
earlier assault, also using razor blades, on two black inmates.
The District Court denied the motion without ordering the
government to produce discovery or holding a hearing.

        Also before trial, the government filed motions in
limine for a hearing on, and then to preclude altogether,
Taylor‟s justification defense. The government argued that
Taylor‟s evidence, which consisted of testimony from Taylor,
several fact witnesses, and an expert on prison culture and
would have described the racial tensions in the prison and
asserted that Bistrian‟s threats against Taylor justified the
attack, failed to establish the defense as a matter of law.




                              5
      In this Circuit, the elements of justification are:

             First, that [the defendant] was
             under an immediate, unlawful
             threat of death or serious bodily
             injury to himself or to others;

             Second, that [the defendant] had a
             well-grounded [or reasonable]
             fear that the threat would be
             carried out if he did not commit
             the offense;

             Third, that [the defendant‟s]
             criminal action was directly
             caused by the need to avoid the
             threatened harm and that [the
             defendant] had no reasonable,
             lawful opportunity to avoid the
             threatened      harm      without
             committing the offense; that is,
             that [the defendant] had no
             reasonable lawful opportunity
             both to refuse to do the criminal
             act and also to avoid the
             threatened harm; and

             Fourth, that [the defendant] had
             not recklessly placed himself in a
             situation in which he would be
             forced to engage in criminal
             conduct.

Third Cir. Model Crim. Jury Instr. § 8.04.




                               6
        The District Court held a hearing on November 22,
2010, at which Taylor made an offer of proof. Two days
later, the District Court denied the government‟s motion
without prejudice and decided to allow Taylor to testify. The
Court stated, “I‟m going to allow the defendant to testify to
whatever the defendant is going to testify to. . . . [I]f the
defendant testifies to justification, whether or not I allow the
defendant to call any other witnesses to support that will
depend entirely on what the defendant has to say.” At the
same time, the District Court made clear that it was skeptical
of the merits of Taylor‟s proffer:

              Mr. Cedrone [Taylor‟s attorney],
              as you described [Taylor‟s]
              testimony yesterday, it doesn‟t
              cover all the elements [of a
              justification defense] and the ex
              parte submission you‟ve made
              today . . . also doesn‟t cover all
              the elements. . . . .

              However, I‟m not going to —
              whatever discretion I may have to
              preclude a defendant‟s testimony
              with respect to justification, I‟m
              not going to exercise that
              discretion. I‟m going to allow the
              defendant to testify, tell his story,
              and at the conclusion of his
              testimony we will revisit the issue
              of whether or not you may call
              any witnesses to corroborate that.




                               7
             Just to give you an idea of what
             my thinking is, based on your
             proffer, your proffer does not
             offer a defense of justification. It
             covers, perhaps, one element but
             it certainly doesn‟t cover all the
             required elements.

The government objected to the District Court‟s ruling,
arguing that, because of the lack of support for his defense,
Taylor should not be allowed to testify as to justification.

       At trial, Taylor moved for a judgment of acquittal after
the prosecution rested its case. The District Court denied the
motion. Taylor took the stand and presented his version of
the events surrounding the attack. Before he was allowed to
present additional witnesses, however, the District Court
asked Taylor for a second offer of proof. Taylor proffered the
testimony of five fact witnesses and his prison-culture expert.
None of the proposed witnesses actually saw the assault;
Taylor proposed that they would testify about the earlier
incident with the prison psychiatrist, the resulting racial
tensions, and the fact that Bistrian knew how to escape from
handcuffs and use them as a weapon (to bolster Taylor‟s
theory that Bistrian was more dangerous when cuffed than
when the inmates were pacing together in the yard). After
Taylor‟s proffer, the District Court precluded him from
putting on any of the proffered witnesses. It reasoned as
follows:

             I believe [Taylor] had a
             reasonable lawful opportunity to
             avoid this simply by asking to be
             taken out of the cage. I believe




                              8
that [Taylor] acted recklessly by
remaining in the cage, where
according to [Taylor], he was
being taunted. He was being
taunted a half hour before the
attack, and he remained in the
cage and didn‟t ask to be taken
out.

And so assuming for a moment
that I have to accept the absurd
notion that a man is more
dangerous      and    creates      an
imminent threat when he puts
himself in handcuffs and that
[Taylor‟s] attack on him for . . .

...

Two minutes and thirty-seven
seconds, [Taylor] was attacking
Mr. Bistrian with a deadly
weapon through three cans of OC
spray, I just think you haven‟t
remotely made out justification. I
don‟t think there was an
immediate unlawful threat of
death or serious bodily injury to
himself or others.

I think that taking all the evidence
in the light most favorable to
[Taylor], I don‟t think [Taylor]
thought he was about to attack




                 9
him. I think [Taylor‟s] testimony
is that he was concerned that he
might, and he was going to get
him first.     Taking [Taylor‟s]
testimony as true, I think your
client wanted to do a preemptive
strike, and he thought at some
point, accepting what he says is
true, that Mr. Bistrian was going
to attack him, but certainly not in
that cage, certainly not in that
cage.

And second, that he had a well
grounded fear or a reasonable
belief that the threat would be
carried out if he did not commit
the offense. Each time he cut Mr.
Bistrian, that could be construed
as a separate assault.       And
certainly by the time Mr. Bistrian
was on the ground, and [Taylor]
continued to cut him with the
knife, he couldn‟t possibly have
had a well grounded or reasonable
fear that the threat would be
carried out if he didn‟t keep
knifing him.

But perhaps, perhaps most
significantly, that Mr. Taylor‟s
criminal action was directly
caused by the need to avoid the
threatened harm, and that Mr.




                10
              Taylor had no reasonable lawful
              opportunity      to   avoid     the
              threatened       harm       without
              committing the offense. I think
              he plainly did, and he didn‟t avail
              himself of that opportunity. He
              didn‟t even try. He never asked
              the guard to be taken out. And I
              don‟t think that — I don‟t think he
              availed himself of that reasonable
              lawful opportunity.

              And so although I would allow
              [Taylor] to call Mr. Bistrian
              because he‟s the victim of this
              case, [Taylor has] elected not to
              call Mr. Bistrian, and the other
              witnesses, I believe down to the
              expert, do not provide . . . ,
              accepting everything they say is
              true, don‟t provide [Taylor] with a
              complete defense of justification,
              and so I have the discretion to
              preclude the presentation of that
              defense.

The District Court instructed the jury that the government
bore the burden of proving beyond a reasonable doubt that
Taylor: (1) struck Bistrian intentionally; (2) used a dangerous
weapon, i.e., a razor, as charged in the indictment; (3) acted
with the intent to cause bodily harm; and (4) intentionally
struck Bistrian within the special maritime and territorial
jurisdiction of the United States. The District Court declined




                              11
to provide any instruction concerning a just cause or excuse
for the offense.

        After his conviction, Taylor moved for acquittal and
for a new trial. The District Court issued a 19-page written
opinion denying the motions and explaining, among other
things, its decisions to preclude Taylor from offering
additional witnesses and not to instruct the jury about
justification. In response to Taylor‟s argument that the
absence of just cause or excuse is an element of an 18 U.S.C.
§ 113(a)(3) offense, the District Court concluded that the
absence of just cause or excuse is an affirmative defense to,
not an element of, a § 113(a)(3) violation.

      Taylor now appeals.1

                             II.

       On appeal, Taylor first argues that the District Court
erred in failing to instruct the jury that the absence of just
cause or excuse is an element of an 18 U.S.C. § 113(a)(3)
offense that the government must establish by proof beyond a
reasonable doubt. 18 U.S.C. § 113(a)(3) provides:

             Whoever, within the special
             maritime        and      territorial
             jurisdiction of the United States,
             is guilty of an assault shall be
             punished as follows . . . Assault

1
  The District Court had jurisdiction over this case under 18
U.S.C. § 3231. Our jurisdiction to review the judgment of
conviction arises under 28 U.S.C. § 1291.




                             12
              with a dangerous weapon, with
              intent to do bodily harm, and
              without just cause or excuse, by a
              fine    under     this  title   or
              imprisonment for not more than
              ten years, or both.

(emphasis added). The language of this provision is unique in
the federal assault statute, 18 U.S.C. § 113: of the seven
types of assault listed, only this provision, for assault with a
dangerous weapon, includes a specific reference to “just
cause or excuse.” Although we cannot be sure why Congress
included those words in subsection (a)(3), but not in the other
subsections of the statute, the weight of the authority and
relevant Supreme Court precedent support the District Court‟s
conclusion that they refer to an affirmative defense that the
defendant bears the burden of proving by a preponderance of
the evidence.

        Few cases have discussed this point in any detail. But,
as both parties acknowledge, the great majority of cases
describing the elements of § 113(a)(3) or its predecessor,
§ 113(c), state (without much, or any, supporting analysis)
that a conviction under that subsection requires proof of only
three elements: (1) assault; (2) with specific intent to inflict
bodily harm; and (3) use of a “dangerous weapon.” See, e.g.,
United States v. Herron, 539 F.3d 881, 886 (8th Cir. 2008)
(“The elements of Assault with a Dangerous Weapon require
that the defendant: 1) assault the victim; 2) intend to do
bodily harm; and 3) use a dangerous weapon to commit the
assault.”); United States v. Smith, 520 F.3d 1097, 1101 (9th
Cir. 2008) (stating that assault with a dangerous weapon
under 18 U.S.C. § 113(a)(3) “has three elements: (1) that the
defendant intentionally struck or wounded the victim; (2) that




                              13
the defendant acted with the specific intent to do bodily harm;
and (3) that the defendant used a „dangerous weapon‟”); see
also United States v. Estrada-Fernandez, 150 F.3d 491, 494
(5th Cir. 1998) (per curiam); United States v. Sturgis, 48 F.3d
784, 786 (4th Cir. 1995); United States v. Johnson, 967 F.2d
1431, 1433 (10th Cir. 1992), abrogated on other grounds by
Lewis v. United States, 523 U.S. 155, 162 (1998). These
cases do not list the lack of a just cause or excuse as an
element of the offense.

       Another line of cases acknowledges the statute‟s
“without just cause or excuse” language and explicitly
concludes that the government does not need to plead or
prove the absence of a just cause or excuse to secure a
conviction under § 113(a)(3). The most recent of these, and
the one on which the District Court primarily relied, is United
States v. Guilbert, 692 F.2d 1340 (11th Cir. 1982). In that
case, after reciting the three elements of assault with a
dangerous weapon listed above, the court said, “[t]he
existence of „just cause or excuse‟ for the assault is an
affirmative defense, and the government does not have the
burden of pleading or proving its absence.” Id. at 1343. The
opinion cites a string of cases for that proposition, the most
substantive of which is Hockenberry v. United States, 422
F.2d 171 (9th Cir. 1970). There, the court reasoned:

              It was not necessary [for the
              indictment] to recite that the
              assault was „without just cause or
              excuse.‟ If there was such cause
              or excuse, the defendant could
              show it; the government did not
              have the burden of pleading or
              proving its absence. By a rule of




                              14
              long standing, „an indictment or
              other pleading founded on a
              general provision defining the
              elements of an offense, or of a
              right conferred, need not negative
              the matter of an exception made
              by a proviso or other distinct
              clause, whether in the same
              section or elsewhere, and * * * it
              is incumbent on one who relies on
              such an exception to set it up and
              establish it.‟

Id. at 173 (quoting McKelvey v. United States, 260 U.S. 353,
357 (1922)). Although the reasoning in these cases is not
extensive, they support the District Court‟s conclusion.2

2
   Taylor seeks to distinguish these cases by pointing out that
Hockenberry, which arose out of a challenge to indictment,
concerned which party bears the burden of pleading
justification, not which party bears the burden of proving that
issue. He does not explain the significance of that distinction,
but he presumably intends to argue that, by including the
“without just cause or excuse” language in the statute,
Congress set up a burden-shifting scheme in which the
defendant bears the burden of raising a justification that the
government must then disprove beyond a reasonable doubt.
As we discuss below, the Supreme Court‟s decision in Dixon
v. United States, 548 U.S. 1 (2006), forecloses any such
argument. Moreover, even though Taylor is right that
Hockenberry involved a pleading question, Guilbert did not:
the issue in that case was whether the evidence was sufficient
to support a conviction, which necessarily entails the question




                              15
        To counter all of this authority, Taylor cites a single
case: United States v. Bordeaux, 570 F.3d 1041 (8th Cir.
2009). In Bordeaux, the Eighth Circuit Court of Appeals,
considering a sufficiency-of-the-evidence challenge to a
§ 113(a)(3) conviction, included “acted without just cause or
excuse” in a list of elements of the offense, and analyzed
whether the government “presented sufficient evidence that
Bordeaux acted without just cause or excuse.” Id. at 1047-48.
But the court did not consider whether that element should
more properly be treated as an affirmative defense, and the
government does not appear to have raised the issue.
Additionally, as the government points out here, the court‟s
interpretation of the offense in Bordeaux is inconsistent with
another of its cases from the previous year, in which it
omitted the “just cause or excuse” language from a recitation
of the elements of the offense. See Herron, 539 F.3d at 886.
Given these facts, Bordeaux does not present an especially
compelling counterpoint to the numerous cases suggesting
that “just cause or excuse” is an affirmative defense.3



of the burden of proof. Thus, even if Hockenberry is
distinguishable on the ground Taylor suggests, Guilbert is
not.
3
   United States v. Wycoff, 545 F.2d 679 (9th Cir. 1976),
which Taylor raised in a post-argument submission, is
similarly unhelpful. There, the court merely affirmed a
defendant‟s assault-with-a-dangerous-weapon conviction over
a challenge that the district court failed properly to notify the
defendant of a change in the jury instructions. Id. at 683.
The district court had decided, at the last minute, to include
the absence of just cause or excuse as an element of the




                               16
       Relevant Supreme Court precedent also supports the
District Court‟s interpretation. Specifically, in McKelvey v.
United States, 260 U.S. 353 (1922), the Supreme Court
rejected an argument that the government erred in failing to
charge in an indictment that the defendant did not fall within
an exception contained in the statute.4 It stated:



offense in its instructions. The government did not dispute,
and the court did not analyze, the substance of that decision.
4
  McKelvey involved a charge of unlawfully obstructing free
passage over unoccupied public lands of the United States.
The relevant statute stated:

             That no person, by force, threats,
             intimidation, or by any fencing or
             inclosing, or any other unlawful
             means, shall prevent or obstruct,
             or shall combine and confederate
             with others to prevent or obstruct,
             any person from peaceably
             entering upon or establishing a
             settlement or residence on any
             tract of public land subject to
             settlement or entry under the
             public land laws of the United
             States, or shall prevent or obstruct
             free passage or transit over or
             through     the     public    lands:
             Provided, this section shall not be
             held to affect the right or title of
             persons, who have gone upon,




                             17
             By repeated decisions it has come
             to be a settled rule in this
             jurisdiction that an indictment or
             other pleading founded on a
             general provision defining the
             elements of an offense, or of a
             right conferred, need not negative
             the matter of an exception made
             by a proviso or other distinct
             clause, whether in the same
             section or elsewhere, and that it is
             incumbent on one who relies on
             such an exception to set it up and
             establish it.

Id. at 357. Although McKelvey dealt solely with the
sufficiency of an indictment, the last sentence of the quoted
passage suggests that a defendant relying on an exception
must both raise the exception and “establish it.” In other
words, where the statute contains such an exception, the
defendant bears the burden of proving it.5


             improved or occupied said lands
             under the land laws of the United
             States, claiming title thereto, in
             good faith.

260 U.S. at 356 (quoting 23 Stat. 321 (Comp. St. § 4999)).
5
   We use McKelvey to illustrate our point here because it is
often cited as the source of this rule. See, e.g., Dixon, 548
U.S. at 13-14. In fact, however, numerous Supreme Court
decisions before McKelvey, dating back at least to 1841, held




                             18
        Of course, that is not the end of the analysis: applying
the McKelvey rule in this case naturally begs the question
whether the “just cause or excuse” language in § 113(a)(3)
qualifies as an “exception made by a proviso or other distinct
clause.” Whether a particular statutory phrase constitutes a
defense or an element of the offense under McKelvey turns on
whether “the statutory definition is such that the crime may
not be properly described without reference to the exception.”
United States v. Prentiss, 206 F.3d 960, 973 (10th Cir. 2000)
(citing United States v. Cook, 84 U.S. 168, 173-74 (1872)),
aff’d in relevant part, 256 F.3d 971, 980 (10th Cir. 2001) (en
banc). If so, the exception is an element of the crime. If not,
the exception is a defense. We conclude that, under the plain
language of McKelvey as supplemented by this test, the “just
cause or excuse” is a defense to, rather than an element of,
§ 113(a)(3).

       As McKelvey requires, the “without just cause or
excuse” language in § 113(a)(3) appears in a “distinct
clause,” set off by commas from the rest of the statute. This
alone is not dispositive, however, since the phrase “with


that the party who wishes to rely on an exception to an Act of
Congress must raise it and establish it. See, e.g., Schlemmer
v. Buffalo, Rochester & Pittsburgh Ry., 205 U.S. 1, 10 (1907)
(holding that a defendant who “wishe[s] to rely upon [a]
proviso” bears “the burden . . . to bring itself within an
exception”) (internal quotation marks omitted)) (Holmes, J.);
United States v. Dickson, 40 U.S. 141, 165 (1841) (“In short,
a proviso carves special exceptions only out of the enacting
clause; and those who set up any such exception, must
establish it as being within the words as well as within the
reasons thereof.”).




                              19
intent to do bodily harm,” which does set forth an element,
also appears in a distinct clause. More importantly, the
former clause falls outside of the “definition” test set forth
above because the offense may properly be described as an
“[a]ssault with a dangerous weapon, with intent to do bodily
harm,” without referencing the “just cause or excuse”
language.6 Indeed, as discussed above, most cases that have
identified the elements of the offense have done precisely
that. Thus, we have no problem concluding that the “without
just cause or excuse” language in § 113(a)(3) is an “exception
made by a . . . distinct clause,” such that, under McKelvey, “it
is incumbent on” the defendant, “who relies on” the
exception, “to set it up and establish it.” 260 U.S. at 357.

       Another, more recent Supreme Court case, Dixon v.
United States, 548 U.S. 1 (2006), reinforces our conclusion
that Taylor bore the burden of establishing the existence of a
just cause or excuse in this case. In Dixon, the defendant,
who was indicted and tried on federal firearms charges,
asserted a duress defense. She argued that as the defendant,
she bore the burden of production on the defense, but that the
burden then shifted to the government to disprove it beyond a
reasonable doubt.

       The Supreme Court disagreed. It first concluded that
placing the burden of proving duress on the defendant did not
6
   Taylor effectively concedes this point in his brief, when he
states that the statute “requires the government to prove the
absence of „just cause or excuse‟ when applicable under the
facts of a given case.” Appellant‟s Br. 31 (emphasis added).
If, as Taylor suggests, the “just cause or excuse” language
does not apply in every case, then, plainly, the absence of a
just cause or excuse is not an essential element of the offense.




                              20
violate the Due Process Clause of the Constitution because
proof of duress could “in no way disprove[] an element” of
the firearm-possession charge, including the requisite
“knowing” mens rea. Id. at 7; see also United States v. Dodd,
225 F.3d 340, 344 (3d Cir. 2000) (“Although the Due Process
Clause requires the government to prove all elements of the
charged offense beyond a reasonable doubt, and therefore
requires the government to disprove beyond a reasonable
doubt any defenses that negate an element of the charged
offense, there is no constitutional bar to the defendant‟s
bearing the burden of persuasion on defenses that do not
negate an element of the offense.”).

        The Dixon Court also held that placing the burden of
proving duress on the defendant in that case comported with
federal common law. It noted that, “at common law, the
burden of proving affirmative defenses—indeed, all . . .
circumstances of justification, excuse or alleviation—rested
on the defendant.” Dixon, 548 U.S. at 8 (internal quotation
marks and citations omitted). This rule, the Court went on to
explain, “accords with the general evidentiary rule that the
burdens of producing evidence and of persuasion with regard
to any given issue are both generally allocated to the same
party” and “the doctrine that where the facts with regard to an
issue lie peculiarly in the knowledge of a party, that party has
the burden of proving the issue.” Id. (internal quotation
marks and citations omitted). The Court then reasoned that,
even though the firearm offense statute “does not mention the
defense of duress,” it could “safely assume that the 1968
Congress [that enacted the firearm statute] was familiar with
both the long-established common-law rule and the rule
applied in McKelvey” and that Congress “would have
expected federal courts to apply a similar approach to any




                              21
affirmative defense that might be asserted as a justification or
excuse for violating the new law.” Id. at 13-14 (footnote
omitted). In other words, the Court “presume[d] that
Congress intended the petitioner to bear the burden of proving
the defense of duress by a preponderance of the evidence.”
Id. at 17.

       The same logic applies in this case. The existence of
just cause or excuse does not disprove the elements of assault
under § 113(a)(3), namely, physical attack, intent to do bodily
harm, and use of a dangerous weapon. Accordingly, under
the rule of Dixon and Dodd, placing the burden of proving the
absence of just cause or excuse on the defendant does not run
afoul of the Due Process Clause.

        And, as Dixon makes clear, placing the burden of
proving justification on Taylor in this case also is consistent
with common law and basic principles of statutory
interpretation. The same common-law rule that places the
burden of proving duress on the defendant also applies to
issues involving justification or excuse. Id. at 8. That rule
makes sense here for the same reasons the Court noted in
Dixon: it allocates the burdens of production and persuasion
to the same party, and it places those burdens on the party
with peculiar knowledge of the relevant facts. In this case,
Taylor‟s justification defense depended on his testimony that
he feared that Bistrian would attack him first and that he
feared Bistrian would slip out of his handcuffs and use them
as a weapon. Particularly given its inability to compel Taylor
to testify, the government would have had a difficult time
obtaining that information on its own.

      Moreover, the inference about congressional intent the
Court relied on in Dixon — that, absent some indication to




                              22
the contrary, Congress intended that the “long-established
common-law rule” that the defendant bears the burden of
proving justification or excuse and “the rule applied in
McKelvey” would guide federal courts‟ analyses — applies
with even greater force in this case.7 If we are to presume, as
the Court did in Dixon, that Congress legislates with those
rules in mind, then surely more than a simple reference to a
particular defense, as in § 113(a)(3), is needed to evince
Congress‟s intent to convert a traditional common-law
defense into an element of the government‟s affirmative case.
Indeed, given that the Dixon Court considered the absence of
any reference to a duress defense in the firearm statute to be a
weakness, see, e.g., 548 U.S. at 13-14 (“Even though the Safe
Streets Act does not mention the defense of duress, we can
safely assume that the 1968 Congress was familiar with both
the long-established common-law rule and the rule applied in
McKelvey and that it would have expected federal courts to
apply a similar approach to any affirmative defense that might
be asserted as a justification or excuse for violating the new
law.” (emphasis added) (footnote omitted)), the same
inferences must apply even more forcefully in a case like this
one, in which the statute specifically mentions the defense.
Accordingly, we interpret § 113(a)(3)‟s reference to a
justification or excuse as a reference to common-law


7
  We are aware that McKelvey was decided in 1922, whereas
the relevant statutory language in this case was enacted
earlier, in 1909. But, as noted above, the principle for which
McKelvey stands was established and applied in numerous
pre-1909 Supreme Court decisions. Thus, the substance of
Dixon‟s presumption retains its force in this case.




                              23
justification and excuse defenses, which the defendant bears
the burden of proving by a preponderance of the evidence.8

        We do not lightly dismiss Taylor‟s textual argument,
that reading the statute in this way renders the words “without
just cause or excuse” superfluous because courts have
allowed defendants to raise common-law justification
defenses to the other subsections of § 113 that do not contain

8
   For similar reasons, Dixon also forecloses Taylor‟s
alternative argument that the reference to just cause or excuse
in § 113(a)(3) implies a complicated burden-shifting
paradigm, in which the burden shifts to the government to
disprove justification beyond a reasonable doubt after the
defendant raises the issue and adduces some evidence to
support it. See Appellant‟s Reply Br. 5-6 (citing United
States v. Lawrence, 349 F.3d 109, 122 (3d Cir. 2003)). For
one thing, nothing in the text of the statute suggests such an
approach. It would run counter to Dixon‟s presumption that
Congress legislates with common-law principles in mind to
conclude that Congress intended to set up a burden-shifting
scheme when all it did was use the words “without just cause
or excuse.” More directly, this is precisely the argument that
the Supreme Court rejected in Dixon. Dixon conceded that
she bore the burden of production on her duress defense, 548
U.S. at 4, but argued that “modern common law” requires the
government to disprove affirmative defenses beyond a
reasonable doubt in criminal cases, see id. at 8. The Supreme
Court rejected that argument and applied “[t]he long-
established common-law rule . . . that the burden of proving
duress rests on the defendant” instead. Id. at 15. Taylor has
offered us no reason to conclude, contrary to Dixon, that the
ordinary common-law rule does not govern this case as well.




                              24
that phrase. Indeed, we confess that, given the complete
absence of legislative history and the fact that the language
was first added to the statute in 1909, we cannot be entirely
sure what Congress had in mind. But two additional points
bolster our conclusion that “without just cause or excuse” is
not an element of a § 113(a)(3) offense. First, although
mindful of the general principle that we should avoid
interpretations that effectively read words out of a statute, see,
e.g., Rosenberg v. XM Ventures, 274 F.3d 137, 141 (3d Cir.
2001), we believe that the specific, on-point Supreme Court
cases in this area, McKelvey and Dixon, take precedence over
that broad, generally applicable canon of statutory
interpretation here.

        Second, we question the foundations of Taylor‟s
argument. Taylor presumes that defendants charged with
assaults under subsections of § 113 other than § 113(a)(3)
may pursue common-law defenses, and, indeed, the
government admits that its practice has been not to object to
self-defense or other justification instructions in cases
prosecuted under other subsections of § 113. But the
government‟s practice is not conclusive evidence of
congressional intent. Because “federal crimes are defined by
statute rather than by common law,” United States v. Oakland
Cannabis Buyers’ Coop., 532 U.S. 483, 490 (2001), the
availability of common-law defenses to federal crimes is not a
foregone conclusion, cf. id. at 491 (reserving the question
whether common-law necessity “can ever be a defense when
the federal statute does not expressly provide for it”); see also
Dixon, 548 U.S. at 13 & n.7 (assuming, without deciding, that
common-law duress defense is available to federal statutory
firearm crime). Perhaps, by including the “without just cause
or excuse” language in the predecessor versions of




                               25
§ 113(a)(3), but not in the other subsections of § 113,
Congress intended to make common-law justification and
excuse defenses available for assaults with a dangerous
weapon, but not for the other assault offenses set forth in
§ 113. We need not reach any definitive conclusion on this
issue, however, because we are satisfied that the other reasons
set forth above adequately support our conclusion as to the
meaning of those words in § 113(a)(3).

       In light of McKelvey, Dixon, and for the reasons
discussed above, we agree with the District Court that in this
case the burden of proving a “just cause or excuse” for the
assault rested with Taylor, the defendant.

                              III.

        Taylor raises three additional issues, none of which
warrants reversal. First, Taylor challenges the District
Court‟s exclusion of certain additional witnesses related to his
justification defense and its refusal to instruct the jury on
justification. But, as the District Court correctly found, the
evidence plainly does not support such a defense. Second,
Taylor argues that the District Court infringed his Fifth
Amendment right against self-incrimination by “forcing” him
to testify as a condition precedent to admitting the remaining
evidence of his justification defense. In fact, though, the
District Court did not force Taylor to testify at all, and it
clearly informed him from the outset that the proffered
evidence was insufficient to establish justification as a matter
of law. Third, and finally, Taylor appeals the District Court‟s
denial of his motion to dismiss the indictment for selective
prosecution. Taylor‟s theory here — that he was prosecuted
for an assault on a white inmate, but not for an earlier assault
on two black inmates — does not suggest, let alone provide




                              26
the required “clear evidence” of, discriminatory intent or
effect.

                              A.

        The District Court did not err in precluding Taylor
from offering additional witnesses to support his justification
defense or in refusing to include the defense in its jury
charge. The tests for precluding a defendant from offering a
defense and for denying an instruction on a particular defense
are the same: whether the evidence presented (or proffered)
is legally sufficient to support the defense. See United States
v. Mike, 655 F.3d 167, 175 (3d Cir. 2011) (defendant whose
evidence does not support a particular affirmative defense is
not “entitled” to a jury instruction on that defense); United
States v. Miller, 59 F.3d 417, 421-22 (3d Cir. 1995) (district
court did not err in precluding defendant from offering
evidence of duress where proffered evidence was insufficient
to establish duress as a matter of law); cf. Mathews v. United
States, 485 U.S. 58, 63 (1988) (“As a general proposition a
defendant is entitled to an instruction as to any recognized
defense for which there exists evidence sufficient for a
reasonable jury to find in his favor.” (emphasis added)).

      The District Court properly analyzed Taylor‟s proffer
under the Model Jury Instructions,9 and concluded that his


9
  Taylor‟s argument on appeal that the District Court applied
the wrong test to evaluate his justification defense is
meritless. The model instruction applies broadly across all
types of cases. Moreover, although Taylor argues that the
District Court should have evaluated his defense according to
“general justification principles,” he does not articulate what




                              27
proposed defense did not satisfy any of the required elements,
as follows. First, Taylor was not facing an immediate threat
of attack because Bistrian was handcuffed. Second, Taylor
did not have a reasonable fear that the threat would be carried
out if he did not attack Bistrian. Taylor‟s assertion that
Bistrian was more dangerous in handcuffs, since he knew
how to escape them and use them as a weapon, was belied by
the fact that Taylor did not feel the need to attack Bistrian
when he was handcuffed at the beginning of the recreation
hour. Third, Taylor‟s attack was not directly caused by a
need to avoid harm because it was not made in response to
any immediate threat by Bistrian. Despite Bistrian‟s alleged
verbal threat to Taylor during the recreation time, Bistrian
and Taylor had been pacing together in the same cage without
any physical contact for almost an hour before Taylor
attacked. Moreover, Taylor did not take any steps to avoid
any perceived threat, e.g., he did not report the threats to
prison staff or ask to be removed from the yard at any time.10
Fourth, and finally, by choosing to remain in the yard with
Bistrian, rather than asking the authorities to take him back to
his cell (which the prison guards testified they would have



those principles are or how they differ from the model-
instruction standard the District Court applied.
10
   Also, as the District Court pointed out in its oral decision,
the attack continued for two minutes and thirty-seven
seconds, despite the guards‟ use of three cans of pepper spray,
and only ended when the guards used a “flash bang” grenade
to stun Taylor. All of those facts are inconsistent with
limited, defensive action that is necessary to avoid imminent
harm.




                              28
done), Taylor recklessly placed himself in the situation that
gave rise to the assault.

        The District Court‟s conclusions are manifestly
correct. Moreover, as the District Court also noted, none of
the testimony Taylor proffered would have remedied the
defects the District Court identified. On this record, it is
difficult to imagine any reasonable person reaching a contrary
result.

                               B.

        Taylor argues that the District Court violated his Fifth
Amendment rights by requiring him to take the stand as a
condition precedent to the presentation of his justification
defense. To support his argument, Taylor relies primarily on
Brooks v. Tennessee, 406 U.S. 605 (1972), in which the
Supreme Court held that a Tennessee statute that required
defendants who intended to testify to take the stand as the
first defense witness violated the Fifth Amendment. Noting
that a defendant “cannot be absolutely certain that his
witnesses will testify as expected or that they will be effective
on the stand,” the Court held that the Tennessee statute “cast[]
a heavy burden on a defendant‟s otherwise unconditional
right not to take the stand” by forcing him to testify before the
precise contours of the other witnesses‟ testimony were
known. Id. at 609-11. The same thing happened in this case,
Taylor argues, because the District Court suspended its ruling
on the merits of his justification defense until after he
testified, thereby denying Taylor the choice to remain silent
depending on the testimony of the other witnesses.

      That argument fails on the facts. The District Court
did not force Taylor to testify. Instead, it denied the




                               29
government‟s request to preclude Taylor from testifying.11
And, unlike in Brooks, the District Court here was not
enforcing a blanket rule about defendant‟s testimony; it made
a careful, case-specific and well founded decision after
considering the defendant‟s proffer. Furthermore, the District
Court made clear from the outset, before Taylor testified, that
it did not believe that Taylor‟s testimony, standing alone or as
corroborated by the proposed additional witnesses, would
establish all of the necessary elements of a justification
defense, allowing Taylor to make an informed decision as to
whether he should testify. Thus, this case simply does not
raise the same type of concerns as Brooks.

       Moreover, as the District Court pointed out (and
Taylor‟s counsel acknowledged), the testimony of the other
witnesses, none of whom observed the actual assault, was
offered only to “corroborate or support” Taylor‟s version of
events. Absent Taylor‟s testimony, then, none of the other
witnesses‟ testimony would even have been relevant to the
case.12 Thus, the alternative to the District Court‟s ruling in

11
   Under the circumstances of this case, we need not, and do
not, evaluate the District Court‟s statement that it could have
precluded Taylor from testifying altogether.
12
   In that respect, this case is like United States v. Singh, 811
F.2d 758 (2d Cir. 1987), in which the Second Circuit Court of
Appeals rejected a defendant‟s argument based on Brooks.
There, the district court had precluded the defendant from
pursuing certain lines of cross examination based on hearsay
until the defendant offered a first-hand account of the
underlying events. The Second Circuit concluded that “the
[district] court did not compel appellant to testify at all”;




                               30
this case was not that Taylor would have remained silent until
all of the other witnesses testified, as the Court envisioned in
Brooks; it was that all of the testimony, including Taylor‟s,
would have been excluded.13 We do not find any Fifth
Amendment violation in this case.

                              C.

      Finally, Taylor appeals the District Court‟s decisions
denying his motion to dismiss the indictment for selective
prosecution and denying him discovery on that motion. His
theory is that he was improperly selected for prosecution
because his victim in this case was white. To support that

instead, “[i]t merely refused to accept the proffered testimony
of other witnesses until a proper foundation was laid.” Id. at
762. The same is true here: Taylor‟s testimony provided the
necessary foundation for the testimony of the other proposed
witnesses. See generally Geders v. United States, 425 U.S.
80, 86 (1976) (trial judge in a criminal case “may determine
generally the order in which parties will adduce proof”; “may
refuse to allow cumulative, repetitive, or irrelevant
testimony”; and must “exert substantial control over the
proceedings”).
13
   We note, further, that Taylor did not suffer any prejudice
from the District Court‟s ruling. This is not a case in which
the defendant would have been acquitted absent his
purportedly forced testimony. Because the entire assault was
captured on prison videotape, there was no question as to
what happened or who was responsible for the assault; the
only question was whether Taylor‟s actions were justified.
And, as discussed above, the evidence Taylor proffered on
that issue was legally insufficient to support his defense.




                              31
claim, he pointed out that he was not prosecuted for an earlier
assault on two black victims.

       When analyzing selective prosecution claims, we
review district courts‟ findings of facts for clear error and the
application of legal precepts de novo. United States v.
Schoolcraft, 879 F.2d 64, 67 (3d Cir. 1989). The district
court‟s denial of discovery on such a motion is reviewable for
abuse of discretion. United States v. Hedaithy, 392 F.3d 580,
605 (3d Cir. 2004).

       To establish selective prosecution, the defendant must
“provide evidence that persons similarly situated have not
been prosecuted” and that “the decision to prosecute was
made on the basis of an unjustifiable standard, such as race,
religion, or some other arbitrary factor.” Schoolcraft, 879
F.2d at 68. The defendant bears the burden of proof, id., and
must establish each of these elements with “clear evidence”
sufficient to overcome the presumption of regularity that
attaches to decisions to prosecute, United States v. Armstrong,
517 U.S. 456, 464 (1996). “The required threshold to obtain
discovery” on such a motion is “some evidence tending to
show the existence of the essential elements of the defense,
discriminatory effect and discriminatory intent.” Hedaithy,
392 F.3d at 607 (internal quotation marks omitted).

       Given these high standards, it is clear that the District
Court in this case did not abuse its discretion by denying
Taylor discovery or err in denying his motion to dismiss.
That Taylor was prosecuted for one assault, but not for
another, does not, without more, provide “clear evidence” of
a discriminatory effect or discriminatory intent. Taylor has
not offered any other examples of defendants who assaulted
both white and black inmates, but were only prosecuted for




                               32
assaulting the white inmates. And Taylor-after-the-second-
assault is not “similarly situated” to Taylor-after-the-first-
assault for the obvious reason that the incident that gave rise
to the charges in this case occurred against the backdrop of
Taylor‟s history of disciplinary problems, including the
previous assault on the black inmates. Accordingly, Taylor
did not present sufficient evidence to satisfy the threshold for
obtaining discovery on his selective prosecution claim, let
alone dismissal of the indictment on those grounds, and this
argument does not provide any basis on which we could or
should reverse the judgment of the District Court.

                              IV.

       For the foregoing reasons, we will affirm the judgment
of the District Court.




                              33
