                 This opinion is subject to revision before final
                      publication in the Pacific Reporter

                                 2019 UT 36


                                    IN THE

       SUPREME COURT OF THE STATE OF UTAH

                              STATE OF UTAH,
                                 Appellee,
                                       v.
                        LUCIANO GABRIEL SILVA,
                              Appellant.

                               No. 20161045
                            Filed July 23, 2019

                            On Direct Appeal

                   Second District, Weber County
                   The Honorable Ernest W. Jones
                          No. 151901996

                                 Attorneys:
  Sean D. Reyes, Att’y Gen., Jeffrey D. Mann, Asst. Solic. Gen., Salt
  Lake City, Branden B. Miles, Letitia J. Toombs, Josh B. Wayment,
                        Ogden, for appellee
   Cherise Bacalski, Orem, Emily Adams, Bountiful, for appellant


  ASSOCIATE CHIEF JUSTICE LEE authored the opinion of the Court,
in which CHIEF JUSTICE DURRANT, JUSTICE HIMONAS, JUSTICE PEARCE,
                   and JUSTICE PETERSEN joined.


   ASSOCIATE CHIEF JUSTICE LEE, opinion of the Court:
    ¶1 Luciano Silva was convicted of murder after shooting and
killing his roommate’s friend. He challenges his conviction on this
appeal, asserting that the trial court committed reversible error when
it (1) precluded him from arguing perfect self-defense and
(2) refused to declare a mistrial after the prosecutor asked Silva to
demonstrate the shooting using a facsimile gun. We disagree. Any
error the trial court committed when it refused to allow a claim of
perfect self-defense was harmless. And though we are troubled by
aspects of the demonstration directed by the prosecutor, we cannot
                            STATE v. SILVA
                        Opinion of the Court

say that the trial court abused its discretion when it denied Silva’s
motion for a mistrial. We therefore affirm the conviction.
                                   I
    ¶2 On the night of the shooting, Silva returned home to his
trailer to find his roommate, Fabricio, with a friend, Horacio. Silva
did not know Horacio. But he soon learned that Horacio was
previously a member of the Norteño gang—the same gang Silva
once belonged to.
   ¶3 Silva offered to buy methamphetamine and share it with
Fabricio and Horacio. He made a phone call and arranged for a drug
delivery. While waiting for the delivery, Horacio listened to music
by the Salineros, a group associated with the Norteños. Silva
questioned Horacio about the music before going to his bedroom.
There he mentioned to Fabricio that he was bothered by the music.
And he cleaned some bullets for his gun—a gun that he had
purchased illegally, allegedly for protection from his former gang.
    ¶4 Silva eventually learned that the drug delivery had failed.
Undeterred, he decided to walk to another seller’s home. Silva first
asked Fabricio to accompany him. But Fabricio said he wasn’t
interested in going. So Silva asked Horacio to accompany him and
he did. About ten to fifteen minutes later, Silva returned home alone
without any drugs. He claimed that Horacio had left him at some
point during the walk.
   ¶5 The next morning, Horacio’s body was found with a
gunshot wound to the back of the head. While police were trying to
identify Horacio, Silva and Fabricio went to Walmart to buy some
groceries. On the way there, Silva admitted to Fabricio that he had
shot Horacio in the back of the head. And he explained that he shot
him because he was listening to Norteño music.
   ¶6 Police eventually identified Horacio using his cell phone.
They also discovered a photo from Horacio’s Facebook account that
showed the license plate of a vehicle registered to Silva’s address. So
an officer was assigned to observe Silva’s trailer.
   ¶7 Later that day, Silva left his trailer to go pick up his
daughter. He was immediately approached by the police. They
asked if he knew Horacio, and at first he lied. But he eventually
admitted he knew him but not well. And he agreed to go to the
police station for further questioning. At the station, Silva again
concealed the truth in his initial interactions with the police. But he
eventually came clean. He told the police that he and Horacio were
on their way to purchase drugs when Horacio discovered that he
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was carrying a gun. He said that Horacio had asked him if he could
hold the gun, that Silva had handed it over, and that Horacio had
then turned the gun on Silva and asked to see the money that Silva
had brought to purchase drugs. Silva indicated that he had knocked
the gun out of Horacio’s hand, pushed Horacio back, gained control
of the gun, and fired a shot at the back of Horacio’s head. After
shooting Horacio, Silva said he had thrown the gun into a nearby
river and then went home and hid the clothes he was wearing under
his bed.
    ¶8 When asked about the details of the shooting, Silva admitted
that he knew Horacio was facing away from him when he shot him
and that Horacio was unarmed. But he stated that Horacio was
turning towards him when he shot him. He also told police that he
felt “comfortable” just before the shooting. And he acknowledged
that instead of shooting Horacio he could have ran away or “pointed
the gun at him and walked away.”
    ¶9 The State charged Silva with first-degree murder, two counts
of obstructing justice (for his efforts to hide the gun and his
clothing), and one count of possession of a firearm by a restricted
person (because Silva is an illegal alien). Before trial, the State moved
pursuant to Utah Code section 76-2-402(2)(a)(ii) to preclude the jury
from considering perfect or imperfect self-defense. That section
prohibits a person from using force in self-defense if the person “is
attempting to commit, committing, or fleeing after the commission
or attempted commission of a felony.” UTAH CODE
§ 76-2-402(2)(a)(ii) (2017).1 The State argued that the felonious
conduct Silva was engaged in when he killed Horacio was
(1) attempted possession of methamphetamine and (2) possession of
a firearm by a restricted person. See id. §§ 58-37-8, 76-10-503(2)(a)
(2014) (defining respectively the crimes of possession of a controlled
substance and possession of a firearm by a restricted person).2 Silva

__________________________________________________________
   1  We cite the 2017 version of the statute, while noting that this
section was amended in 2018, see UTAH CODE § 76-2-402(2)(a)(ii)
(2018), because the incident giving rise to this case occurred in
September 2015.
   2  Section 58-37-8 was amended in 2015. Under the amended
statute a first or second conviction of possession of a Schedule I or II
controlled substance constitutes a class A misdemeanor. UTAH CODE
§ 58-37-8(2)(b)(ii) (2015). That amendment, however, did not take
                                                        (continued . . .)
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                         Opinion of the Court

conceded that he was an illegal alien in possession of a firearm. But
he argued that the statute as applied to him unconstitutionally
infringed his right to self-defense. He also argued that the statute
should not apply because he was not attempting to purchase drugs
or fleeing from such an attempt when the shooting occurred. The
trial court rejected both arguments. It ruled that the jury could not
consider perfect self-defense because Silva was “involved in two
felonies at the time of the homicide”—the two identified by the State.
Yet “while [Silva] [was] not entitled to claim ‘perfect’ self-defense,”
the court allowed him to argue “‘imperfect’ self-defense to the jury.”
    ¶10 At trial, Silva largely retold the narrative he provided to the
police. But his testimony varied in key ways. He testified that he felt
scared, rather than comfortable, just before he shot Horacio. And he
stated that he was not sure whether Horacio was facing towards or
away from him when he shot him. He also testified that he thought
Horacio may have had a weapon at the time he shot him,
contradicting his prior statement. He maintained, however, that
Horacio was turning towards him when he shot him. And he again
conceded that he had other options besides shooting Horacio,
including throwing the gun out of Horacio’s reach or simply running
away.
    ¶11 During cross-examination, the prosecutor gave Silva a
“facsimile gun” and asked him to “demonstrate exactly how [he]
was holding the gun when [he] shot Horacio.” The prosecutor then
separated himself some distance from Silva, turned away from him,
and asked him if he thought his life was in danger. Silva said no. The
prosecutor repeated this question two more times while slowly
turning towards Silva. And Silva reaffirmed both times that he did
not feel in danger. Silva’s counsel interjected, noting “for the record”
that the prosecutor “had his back turned and then he turned around
forward and then held his hands up.” He also noted the differences
between the courtroom setting and the setting of the shooting—
specifically that they were “in a courtroom . . . with bailiffs, et
cetera.” During re-examination, Silva clarified that he did not feel in
danger during the demonstration because he was in a courtroom; he
misunderstood that the prosecutor was speaking of the night he
killed Horacio.



effect until October 1, 2015, after the incident giving rise to this case.
We accordingly refer to the 2014 version of the statute.


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                         Opinion of the Court

    ¶12 Following Silva’s testimony, his trial counsel moved for a
mistrial. Counsel asserted that it was “horrendously prejudicial” for
the jury to see the reenactment and a gun in Silva’s hand and that the
demonstration should have been disallowed under Utah Rule of
Evidence 403. The prosecutor responded that Silva’s “actions [were]
central to the issues of this case.” He further argued that Silva never
denied the fact that he had held a gun or killed Horacio. So “[t]he
fact that he held a plastic gun in court in an effort to aid the jury in
understanding what happened . . . was relevant and not prejudicial.”
The trial court agreed with the prosecutor. It denied the motion for a
mistrial, stating that the demonstration was not “prejudicial at all”
but was rather “central to the whole case.” The jury ultimately
convicted Silva on all counts. He appealed the murder conviction to
this court. We initially transferred the matter to the court of appeals
but later vacated the transfer and recalled the appeal.
                                   II
   ¶13 On appeal, Silva argues that the trial court committed two
principal errors. He first asserts that the trial court erred when it
prevented him from arguing perfect self-defense. Second, he asserts
that the court abused its discretion when it denied his motion for a
mistrial based on the prosecutor’s gun demonstration.
    ¶14 We disagree with Silva and thus affirm his conviction. Even
if we assume that the trial court erred when it refused to offer the
perfect self-defense instruction, such error was harmless because it
didn’t result in prejudice to Silva. And though we find aspects of the
prosecutor’s demonstration troubling, we affirm the trial court’s
decision to deny Silva’s motion for a mistrial. Our decision is driven
by the standard of review, the relevancy of the demonstration, the
lack of record evidence, and the opportunities afforded defense
counsel to clarify Silva’s testimony. We advise future attorneys,
however, to proceed cautiously when considering the propriety of a
demonstration like the one here. Requiring a criminal defendant to
hold a facsimile gun is not per se a violation of rule 403 of the Utah
Rules of Evidence. But such a demonstration certainly has the
potential to run afoul of that rule and to trigger a mistrial.
                                   A
   ¶15 Silva first asserts that the trial court erred in precluding him
from arguing perfect self-defense at trial. The governing statute is
Utah Code section 76-2-402(2)(a)(ii). That statute prohibits a person
from using force in self-defense if the person “is attempting to
commit, committing, or fleeing after the commission or attempted

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                         Opinion of the Court

commission of a felony.” UTAH CODE § 76-2-402(2)(a)(ii) (2017). The
trial court refused to instruct the jury on perfect self-defense on the
ground that Silva was engaged in two felonious acts at the time he
killed Horacio—attempted possession of methamphetamine under
Utah Code section 58-37-8 and possession of a firearm by a restricted
person under Utah Code section 76-10-503(2)(a).
    ¶16 Silva challenges the trial court’s refusal to give a perfect
self-defense instruction on three grounds: (1) the statute infringes his
constitutional right to equal protection by foreclosing an allegedly
fundamental right of self-defense for illegal aliens without an
adequate justification; (2) there was insufficient evidence that Silva
was attempting to purchase drugs at the time of the shooting; and
(3) his trial counsel was ineffective in failing to argue that it would
be absurd to interpret the statute to foreclose a right of self-defense
even when there is no connection between the underlying felony and
the act of self-defense.
    ¶17 These claims are not insubstantial. First, Silva plausibly
asserts that the right of self-defense is “fundamental” and raises
serious questions about the sufficiency of the government’s
justification for foreclosing that right for illegal aliens. On the second
point, Silva raises significant questions about the nature of the
alleged “attempt” to purchase drugs, and whether he was in the
course of committing such a crime when the shooting occurred. And
the third point implicates an important question about the
appropriate standard for assessing ineffective assistance of counsel
claims under Strickland v. Washington, 466 U.S. 668 (1984).
    ¶18 Silva’s ineffective assistance of counsel claim focuses on his
trial counsel’s failure to seek to limit the reach of Utah Code
section 76-2-402(2)(a)(ii) on the basis of the doctrine of absurdity. In
Silva’s view, trial counsel was ineffective in failing to assert that it
would be absurd to extend the statutory bar to the use of force in
self-defense where there is no causal connection between the
underlying felony and the self-defense statute.3 The State, for its part,

__________________________________________________________
   3  The statute was amended in 2018 to require such a causal
connection. A criminal defendant is now permitted to argue perfect
self-defense where “the use of force is a reasonable response to
factors unrelated to the commission, attempted commission, or
fleeing after the commission of th[e] felony.” UTAH CODE
§ 76-2-402(3)(a)(ii).


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defends the conduct of trial counsel on the ground that there was no
controlling case law in effect at the time of trial that would have
dictated the argument under the doctrine of absurdity. And the State
cites cases from our court and the court of appeals that suggest that
counsel’s representation must be judged by reference only to settled
law in effect at the time of trial.4 Silva responds by challenging the
viability of this line of cases, and noting that they are inconsistent
with binding precedent from the United States Supreme Court.
    ¶19 We take Silva’s point. A showing of ineffective assistance of
counsel requires proof (1) that trial counsel’s representation “fell
below an objective standard of reasonableness” and (2) that “the
deficient performance prejudiced the defense.” Strickland, 466 U.S. at
687–88. This analysis is conducted under “the presumption that . . .
the challenged action ‘might be considered sound trial strategy.’” Id.
at 689 (quoting Michel v. Louisiana, 350 U.S. 91, 101 (1955)). But the
United States Supreme Court has never said that trial counsel is
categorically excused from failure to raise an argument not
supported by existing legal precedent. In fact, the Court has said just
the opposite. In Padilla v. Kentucky, 559 U.S. 356 (2010), the Court
held that an attorney’s representation fell below an objective
standard of reasonableness notwithstanding the fact that no
precedent at that time established that an attorney has a duty to
inform a defendant about the immigration consequences of a plea.
So it cannot be that we judge an attorney’s performance based only
on settled law.
    ¶20 We thus repudiate the language in our case law limiting our
review of an attorney’s performance to the law in effect at the time of
trial. Ineffective assistance of counsel claims are premised on the
protections provided by the Sixth Amendment of the United States

__________________________________________________________
   4   See State v. Dunn, 850 P.2d 1201, 1228 (Utah 1993) (“[A]
defendant bears the burden of demonstrating why, on the basis of
the law in effect at the time of trial, his or her trial counsel’s
performance was deficient.”); State v. Bruun, 2017 UT App 182, ¶ 68,
405 P.3d 905 (“[C]ounsel is not ineffective for failing to advance a
theory or interpretation of the law which has not yet been settled or
ruled upon by our courts.”); State v. Edgar, 2017 UT App 53, ¶ 10, 397
P.3d 670 (“Counsel ‘cannot be faulted for failing to advance a novel
legal theory which has never been accepted by the pertinent courts.’”
(citation omitted)).


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                         Opinion of the Court

Constitution. Strickland, 466 U.S. at 685–86.5 The standards for
adjudicating such claims are thus a matter of federal law. And it is
not our prerogative to establish doctrines that contradict binding
precedent from the United States Supreme Court. With this in mind,
we now concede that we were wrong to suggest that we may assess
the reasonableness of defense counsel’s performance only in light of
the law in effect at the time of trial. “The proper measure of attorney
performance remains simply reasonableness under prevailing
professional norms.” Id. at 688.
    ¶21 The fact that Silva has raised serious claims on the merits is
not alone sufficient to sustain reversal, however. We can assume for
the sake of argument that Silva’s three claims may have merit—that
there may arguably be an equal protection problem with the
statutory bar on an illegal alien’s use of force in self-defense, that
Silva may not have been in the course of attempting to purchase
drugs when he killed Horacio, and that counsel’s performance fell
below an objective standard of reasonableness. Yet even assuming
these errors, we can reverse Silva’s conviction only if the errors are
prejudicial. See State v. Reece, 2015 UT 45, ¶ 21, 349 P.3d 712. And we
are convinced that they are not.
    ¶22 The prejudice standards implicated here are overlapping but
somewhat different. For preserved constitutional claims—like Silva’s
equal protection claim—the State bears the burden of demonstrating
that the constitutional error was harmless beyond a reasonable
doubt.6 In contrast, for unpreserved constitutional claims—like
Silva’s ineffective assistance of counsel claim—the burden of
demonstrating prejudice rests on the defendant.7 The same goes for
__________________________________________________________
   5  See also Gideon v. Wainwright, 372 U.S. 335, 342–45 (1963)
(incorporating the right to effective assistance of counsel against the
states).
   6  See Chapman v. California, 386 U.S. 18, 24 (1967) (“Certainly error,
constitutional error . . . casts on someone other than the person
prejudiced by it a burden to show that it was harmless. . . . [B]efore a
federal constitutional error can be held harmless, the court must be
able to declare a belief that it was harmless beyond a reasonable
doubt.”); State v. Bond, 2015 UT 88, ¶¶ 37–38, 361 P.3d 104
(articulating this same standard).
   7 See United States v. Olano, 507 U.S. 725, 734 (1993); Strickland, 466
U.S. at 693–96; Bond, 2015 UT 88, ¶ 46.


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Silva’s insufficiency of the evidence claim—he bears the burden of
demonstrating that this error was prejudicial. See State v. Robertson,
932 P.2d 1219, 1227 (Utah 1997), overruled on other grounds by State v.
Weeks, 2002 UT 98, ¶ 25 n.11, 61 P.3d 1000.
    ¶23 We conclude that there is a lack of prejudice here under any
of the above standards. The failure to give a perfect self-defense
instruction was harmless under any of the above formulations.
    ¶24 We begin by emphasizing the substantial overlap between
the defenses of imperfect and perfect self-defense. Imperfect
self-defense is a strict subset of perfect self-defense. So if a theory of
imperfect self-defense is rejected by a jury—as was the case here—it
may logically follow that a theory of perfect self-defense would
likewise be rejected.
    ¶25 Self-defense is an affirmative defense that justifies “using
force against another when and to the extent that the person
reasonably believes that force . . . is necessary to defend the
person . . . against another person’s imminent use of unlawful force.”
UTAH CODE § 76-2-402(1)(a) (2017). Self-defense may be perfect or
imperfect. Perfect self-defense is a complete justification and bars a
conviction. See id. It applies when a defendant reasonably believes
that unlawful force against him is imminent and he is legally justified
in using force to defend himself. Imperfect self-defense is a partial
justification. It reduces a murder charge to manslaughter when a
defendant reasonably, but mistakenly, believes “that the
circumstances provided a legal justification or excuse” for the use of
deadly force. Id. § 76-5-203(4)(a).
    ¶26 “[F]or both perfect and imperfect self-defense, the same
basic facts [are] at issue.” State v. Low, 2008 UT 58, ¶ 32, 192 P.3d 867
(second alteration in original) (quoting State v. Spillers, 2007 UT 13,
¶ 23, 152 P.3d 315) (internal quotation marks omitted). Both “require
the defendant to present the same evidence: that the defendant had a
reasonable belief that force was necessary to defend himself.” Id. The
only difference between the two defenses is that a defendant arguing
perfect self-defense must show that the use of deadly force was
legally justifiable under the circumstances. Id.
    ¶27 The jury here was presented with the theory of imperfect
self-defense. And it rejected that theory. Because the jury rejected the
notion that Silva reasonably but mistakenly believed that deadly force
was necessary, there is a strong argument that the jury likewise
would have rejected the notion that Silva reasonably and correctly
believed that such force was necessary. This argument is bolstered

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                         Opinion of the Court

when we consider the substantial evidence undermining Silva’s
claim of self-defense. Infra ¶¶ 30–32. In light of this evidence, we
may assume that the trial court erred when it refused to allow Silva
to argue perfect self-defense but nonetheless affirm on the basis of a
conclusion that any such error was harmless.
    ¶28 Silva challenges this logic. He claims that a reasonable jury
could reject imperfect self-defense but endorse perfect self-defense.
He bases that assertion on alleged confusion about the distinction
between perfect and imperfect self-defense, which in his view was
reflected in the instruction given to the jury in this case.
    ¶29 We disagree. The line between perfect and imperfect
self-defense is subtle but clear.8 Perfect self-defense requires that a
defendant’s belief that force is necessary be both reasonable and
legally justified. Imperfect self-defense, meanwhile, requires only
that the defendant’s belief be reasonable. The jury instruction in this
case accurately reflected this distinction and correctly explained the
parameters the defense: “Imperfect self-defense . . . applies when the
defendant caused the death of another while incorrectly, but
reasonably, believing that his conduct was justified.” This was an
accurate statement of law. And Silva has identified no basis for a
determination that the jury in this case must have misunderstood the
law of imperfect self-defense.
    ¶30 Silva’s argument, moreover, runs into a brick wall of
evidence—the evidentiary record at trial. We assess the question of
prejudice in light of all the evidence presented at trial. See Reece, 2015
UT 45, ¶ 40. And here the State presented substantial evidence
confirming Silva’s guilt—and undermining his assertion of imperfect
self-defense. First is Silva’s testimony, which was inconsistent and
undermined his claim of self-defense. Silva initially told police that
he knew Horacio was facing away from him when he shot him. But
at trial he said he was unsure which way Horacio was facing. He

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   8  In so stating we do not mean to suggest that the legal lines in
this field are always straightforward. The experienced trial judge in
this case referred to the imperfect self-defense jury instruction as
“the most confusing . . . concept [he’d] ever dealt with.” Hopefully
our opinion in this case will help alleviate some of the confusion. We
also note that the Judicial Council’s Model Utah Jury Instructions
Committee has recently added model instructions on imperfect
self-defense. See MUJI 2d CR 1450–52.


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also told police that he knew Horacio was unarmed. Yet he told the
jury that he was unsure of that fact. Silva claimed at trial that it was
too dark to see which way Horacio was facing. But he claimed that
he could see several other details that night, including the gun
pointed at his chest, which way Horacio’s hat was facing, the gun on
the black asphalt, and the shot in the back of Horacio’s head. And
Silva conceded at trial that he had other options besides shooting
Horacio including throwing the gun out of Horacio’s reach or
running away.
    ¶31 Silva’s trial testimony is also undermined by the statements
he made to his roommate, Fabricio. He initially told Fabricio that
Horacio left him some time during their walk to purchase drugs. His
story changed the next day when he admitted that he killed Horacio.
But he never claimed to have acted in self-defense. Rather he told
Fabricio that he shot Horacio because Horacio had been listening to
Norteño music.
    ¶32 The physical evidence further undermines Silva’s claim of
self-defense. Horacio was shot in the back of the head. And the bullet
went straight through, suggesting that Horacio was facing away
from Silva when he was shot, not turning, and thus not in a position
to cause imminent harm to Silva. Nor was there any indication in the
record of a struggle between Silva and Horacio over the gun—no
evidence of any injury to either (other than the fatal shot to Horacio’s
head), or any other basis for the jury to conclude that there was a
struggle. All of this suggests that even if Silva had been allowed to
argue perfect self-defense, the jury likely would have convicted him
of murder anyway.
    ¶33 Silva proffered a final basis for establishing prejudice during
oral argument to this court. His counsel asserted that the reasonable
belief required for perfect self-defense is different from the
reasonable belief required for imperfect self-defense. And he claimed
that the jury might thus have found in his favor had he been allowed
to present a theory of perfect self-defense. This assertion fails on two
counts. The first problem is one of timing. This argument was raised
for the first time at oral argument, and “[w]e do not address issues
raised for the first time during oral argument.” Porenta v. Porenta,
2017 UT 78, ¶ 33, 416 P.3d 487. The second problem is more
substantive. The argument is premised on a misstatement of our law.
The difference between perfect and imperfect self-defense goes to
legal justification, not the standard of reasonable belief. Imperfect
self-defense requires a “reasonable belief that the circumstances
provided a legal justification or excuse for the conduct although the

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                         Opinion of the Court

conduct was not legally justifiable or excusable under the existing
circumstances.” UTAH CODE § 76-5-203(4)(a) (emphasis added).
Perfect self-defense similarly requires a “reasonable belief,” but it
also requires that the use of force be legally justifiable under the
circumstances. See id. § 76-2-402 (2017); State v. Low, 2008 UT 58, ¶ 32,
192 P.3d 867. The standard for “reasonable belief” is the same for
both defenses. The difference goes only to whether the acts of
self-defense were “legally justifiable.” And Silva’s last argument
would thus also fail even if we were to reach it.
    ¶34 For these reasons we decline to reach the merits of Silva’s
arguments regarding his right to assert perfect self-defense. We
conclude that even if he was entitled to a perfect self-defense
instruction, there is no reasonable likelihood that the trial would
have turned out differently if the jury had been instructed on that
defense. The State has demonstrated harmlessness beyond a
reasonable doubt. The alleged errors are thus harmless under any of
the prejudice standards implicated here. See supra ¶ 22.
                                   B
    ¶35 Silva’s second contention is that the trial court abused its
discretion when it refused to grant a mistrial after the prosecutor
conducted a demonstration using a facsimile gun. We disagree. Our
decision is largely driven by the deferential standard of review. We
note below some concerns we have with such demonstrations and
advise the bench and bar to carefully consider whether such
demonstrations comply with the demands of our rules of evidence.
But we affirm because we conclude that the trial court did not abuse
its discretion in the circumstances of this trial.
    ¶36 We review the denial of a motion for a mistrial under an
abuse of discretion standard. State v. Vargas, 2001 UT 5, ¶ 44, 20 P.3d
271. And “[w]e will not find such abuse unless ‘the incident so likely
influenced the jury that the defendant cannot be said to have had a
fair trial.’” Id. (citation omitted). Here we find no such abuse of
discretion.
   ¶37 The demonstration, for starters, had some probative value.
The critical question for the jury to decide was whether Silva
reasonably believed that he was justified in shooting Horacio. And
whether Silva’s belief was reasonable turned, at least in part, on facts
demonstrated by the prosecutor—as to the way Silva held the gun
and the relevant positions of Silva and Horacio. We thus can
understand why the trial court stated that the demonstration was
“central to the whole case.”

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    ¶38 At the same time, we are skeptical of the trial court’s
sweeping statement that the demonstration was not “prejudicial at
all.” Seeing a gun in the hands of a defendant will often prejudice the
jury against him. This is true even where there is no question that the
defendant used a gun to commit the alleged crime, as is the case
here. This concern, nonetheless, does not warrant overturning the
trial court’s decision.
    ¶39 First we don’t have evidence in the record establishing what
the facsimile gun looked like. And that could make a difference. Use
of a plastic water gun, for example, is less likely to prejudice the jury
against the defendant than the use of a real firearm, or a highly
realistic facsimile. Though the gun used here may have resembled
something closer to a real gun, the record is devoid of detail. We
similarly lack evidence regarding the details of the demonstration
itself. Silva claims that the prosecutor repeatedly taunted him in
front of the jury. Having reviewed an audio recording of the trial, we
are skeptical of this claim. Admittedly, we were not privy to the
details of the demonstration. Yet the trial judge was. And he
determined that the probative value of the demonstration was not
substantially outweighed by a danger of unfair prejudice. See UTAH
R. EVID. 403. That determination is entitled to substantial deference.
See State v. Allen, 2005 UT 11, ¶ 39, 108 P.3d 730 (explaining that a
district judge “is in an advantaged position to determine the impact
of courtroom events on the total proceedings” and applying an
abuse of discretion standard of review).
    ¶40 The trial court also gave defense counsel an opportunity to
clarify the factual differences between the demonstration and the
shooting. And Silva testified that his responses to the prosecutor’s
questioning about whether he felt in danger during the
demonstration were only meant to convey that he did not feel in
danger at that exact moment; he did feel in danger at the time of the
shooting. These clarifications soften the potential prejudice the
defendant may have faced as a result of the demonstration.
    ¶41 We reiterate that our decision is largely a result of the
standard of review. We affirm the trial court’s decision because we
are unpersuaded that it abused its discretion, or that the
demonstration “so likely influenced the jury that the defendant
cannot be said to have had a fair trial.” Vargas, 2001 UT 5, ¶ 44
(citation omitted) (internal quotation marks omitted). Under
different circumstances we might reach a different conclusion. As
this case proves, permitting a demonstration in which a defendant
holds a facsimile gun does not per se violate rule 403 and justify a

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                           STATE v. SILVA
                        Opinion of the Court

mistrial. But there is a risk that such a demonstration could. And we
emphasize that our decision here is not a green light to the use of
gun demonstrations at any trial going forward.
                                 III
   ¶42 We affirm Silva’s conviction for the reasons stated above.
We also affirm the trial court’s decision to deny Silva’s motion for a
mistrial, while emphasizing that our decision on that point is largely
a product of the deferential standard of review.




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