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              STATE OF CONNECTICUT v.
                 LATASHA R. O’BRYAN
                     (SC 19336)
 Rogers, C. J., and Palmer, Zarella, Eveleigh, McDonald, Espinosa and
                             Robinson, Js.
   Argued December 2, 2014—officially released September 15, 2015

  Neal Cone, senior assistant public defender, for the
appellant (defendant).
  Sarah Hanna, assistant state’s attorney, with whom,
on the brief, were Michael Dearington, state’s attorney,
and Laura DeLeo, assistant state’s attorney, for the
appellee (state).
                          Opinion

   ROBINSON, J. This appeal presents numerous issues
concerning the self-defense statute, General Statutes
§ 53a-19,1 and particularly the combat by agreement
disqualification under § 53a-19 (c) (3). The defendant,
Latasha R. O’Bryan, appeals2 from the judgment of con-
viction, rendered after a jury trial, of assault in the
second degree in violation of General Statutes § 53a-60
(a) (2), and attempt to commit assault in the first degree
in violation of General Statutes §§ 53a-49 (a) (2) and
53a-59 (a) (1). On appeal, the defendant claims that the
trial court improperly instructed the jury that: (1) with
respect to the subjective portion of the self-defense
analysis, the defendant was required to have an ‘‘hon-
est’’ or ‘‘sincere’’ belief that physical force was going to
be used against her; (2) she was required to demonstrate
that she had actual knowledge, rather than merely a
reasonable belief, that the victim had violated the terms
of their combat by agreement; and (3) the defendant
retained the burden of proof once the state asserted a
theory of combat by agreement. The state disagrees,
and posits, as an alternative ground for affirmance, that
the defendant was not harmed by any of the claimed
improprieties in the jury instruction because any defen-
dant who is a party to combat by agreement is com-
pletely disqualified from relying on the justification of
self-defense, even if the other combatant escalated the
violence beyond the terms of the agreement. We con-
clude that the trial court properly instructed the jury.
Accordingly, we affirm the judgment of the trial court.
   The record reveals the following facts, which the jury
reasonably could have found,3 and procedural history.
The defendant and the victim, Lawanda McCrea, lived
in different units within the same apartment building
in New Haven. The defendant and the victim had pre-
viously been friendly but, in the months leading up to
the Memorial Day weekend of 2010, their relationship
had deteriorated significantly.4 The friction between
them had become so great that the defendant had com-
plained twice to their landlord, Merwin Wade, about
the victim, saying that ‘‘if she keeps messing with me,
[I’m going to] beat the shit out of her,’’ and that ‘‘it’s
getting out of hand now . . . and if she keep[s] both-
ering me, I’m [going to] whup her butt.’’
  After midnight on May 30, 2010, the victim and her
cousin, Whitney Nichols, left a cookout and drove to
the apartment building. Upon arriving at her building,
the victim saw several people on the porch, including
the defendant, who had just returned home from a dou-
ble shift at her job as a nurse’s aide. Given the animosity
between them, the victim was concerned that the defen-
dant would start a fight with her. Rather than park their
vehicle, the victim and Nichols pulled away and stopped
around the corner from the building. The victim then
called her uncle, William Murdock, and asked him to
help her get into her apartment safely because she was
worried that she might be ‘‘jumped’’ by the defendant
and the others on the porch. If there was going to be
a fight, the victim testified, she did not want anyone
assisting the defendant.
   A few minutes later, Murdock and Wanda Atkins, the
victim’s aunt, arrived to accompany the victim into her
apartment. The victim and her family members then
exited their vehicles and began walking up to the build-
ing. Murdock was angry that his niece felt threatened
and had a heated exchange with the people gathered
on the porch. David Kennedy, another building resident,
came outside when he heard the raised voices and, after
speaking with Murdock, returned inside to wake up
Wade. Murdock, who the defendant testified appeared
intoxicated, then argued with the defendant, and then
the defendant and the victim exchanged words, raising
their voices and cursing at each other.5 The defendant
told the victim that she wanted a ‘‘fair one.’’6 As the
victim testified, ‘‘[the defendant] and I both wanted to
fight each other.’’ Because the victim was wearing a
sundress and sandals, she went up to her apartment to
change into ‘‘appropriate fighting attire.’’
  Meanwhile, Wade, having been apprised of the devel-
oping situation by Kennedy, went outside and directed
everyone who did not live in the building to get off the
porch. As the victim returned downstairs, she met Wade
and explained to him what was happening. Wade told
the victim to ‘‘just leave it alone’’ because he did not
want any fighting to take place.
   Notwithstanding Wade’s instructions, the victim went
out to the porch at the same time that the defendant
returned with her cousin, Tiny Lester. The victim said
to the defendant, ‘‘you want your fair one,’’ and then
walked to meet the defendant on the sidewalk. The
defendant approached the victim and reiterated that
she ‘‘want[ed] [her] fair one.’’ The defendant raised her
fists in a fighting stance and the victim did the same.
The victim testified that she had no weapons with her,
although the defendant provided a different account,
stating that she saw the victim with a lime green colored
sharp object just as the fight started.
   The defendant swung first with her right hand, strik-
ing the victim with a small steak knife that she carried
for both work and self-defense purposes, and the victim
swung back with her right hand, while her left hand
was up in a defensive position. The victim never hit the
defendant because she heard Wade start to scream. The
victim looked down and realized she had blood on her
left hand and yelled, ‘‘I’m cut.’’ Atkins started screaming
that she had seen the blade and that she was calling
911. The defendant denied having cut the victim, yelling
that the victim must have cut herself or that maybe her
fingernails cut the victim.7 At that point, the fight ended
and the victim returned to the building.
  As she was walking up to her apartment, the victim
realized that her shirt and entire right breast area were
soaked in blood. Murdock drove her to the hospital,
where she received treatment for a chest wound four
centimeters long and nine to ten centimeters deep. The
defendant was arrested, but the knife was never
recovered.8
   The state charged the defendant with assault in the
second degree in violation of § 53a-60 (a) (2), and
attempt to commit assault in the first degree in violation
of §§ 53a-49 (a) (2) and 53a-59 (a) (1). The case was
tried to a jury, which rejected the defendant’s claim of
self-defense and found her guilty on all counts. The trial
court subsequently rendered a judgment of conviction
in accordance with the jury’s verdict, and sentenced
the defendant to a total effective sentence of five years
imprisonment. This appeal followed.
   On appeal, the defendant raises numerous challenges
to the trial court’s jury instructions on both self-defense
generally, and combat by agreement specifically. The
state concedes that the defendant’s instructional
claims, although unpreserved, are reviewable under
State v. Golding, 213 Conn. 233, 239–40, 567 A.2d 823
(1989), because they were not waived and ‘‘[a]n
improper instruction on a defense, like an improper
instruction on an element of an offense, is of constitu-
tional dimension.’’ (Internal quotation marks omitted.)
State v. Clark, 264 Conn. 723, 729, 826 A.2d 128 (2003).
Thus, in considering the defendant’s instructional
claims, we note that the well established ‘‘test is
whether the charge, read in its entirety, fairly presents
the case to the jury in such a way that injustice is not
done to either party under the established rules of law.
. . . Thus, [t]he whole charge must be considered from
the standpoint of its effect on the [jurors] in guiding
them to the proper verdict . . . and not critically dis-
sected in a microscopic search for possible error. . . .
Accordingly, [i]n reviewing a constitutional challenge
to the trial court’s instruction, we must consider the jury
charge as a whole to determine whether it is reasonably
possible that the instruction misled the jury. . . . In
other words, we must consider whether the instructions
[in totality] are sufficiently correct in law, adapted to
the issues and ample for the guidance of the jury.’’
(Internal quotation marks omitted.) State v. Lavigne,
307 Conn. 592, 599–600, 57 A.3d 332 (2012).
                             I
  We first consider the defendant’s claim that the trial
court incorrectly charged the jury on the subjective
portion of the subjective-objective test for determining
entitlement to self-defense. Specifically, the defendant
contends that the court incorrectly required that she
have an ‘‘honest’’ or ‘‘sincere’’ belief that physical force
was going to be used against her.9 Relying primarily on
United States v. Hardin, 443 F.2d 735 (D.C. Cir. 1970),
the defendant contends that this language is confusing
because it imports a good faith requirement that goes
beyond the ‘‘actual belief’’ required by the subjective
portion of the self-defense analysis. In response, the
state relies on, inter alia, State v. Prioleau, 235 Conn.
274, 664 A.2d 743 (1995), and State v. Clark, supra,
264 Conn. 723, and contends that the use of the terms
‘‘honest’’ and ‘‘sincere’’ is well established in our case
law and pattern instructions because they are ‘‘syn-
onyms of the term ‘actual.’ ’’ We agree with the state,
and conclude that the trial court’s instructions were an
accurate statement of the law of self-defense that could
not have misled the jury.
   We begin with a ‘‘brief review of the law of self-
defense. Under our Penal Code, self-defense, as defined
in [General Statutes] § 53a-19 (a) . . . is a defense,
rather than an affirmative defense. . . . Whereas an
affirmative defense requires the defendant to establish
his claim by a preponderance of the evidence, a properly
raised defense places the burden on the state to dis-
prove the defendant’s claim beyond a reasonable doubt.
. . . Consequently, a defendant has no burden of per-
suasion for a claim of self-defense; he has only a burden
of production. That is, he merely is required to introduce
sufficient evidence to warrant presenting his claim of
self-defense to the jury. . . . Once the defendant has
done so, it becomes the state’s burden to disprove the
defense beyond a reasonable doubt. . . . Accordingly,
[u]pon a valid claim of self-defense, a defendant is enti-
tled to proper jury instructions on the elements of self-
defense so that the jury may ascertain whether the state
has met its burden of proving beyond a reasonable
doubt that the assault was not justified. . . . As these
principles indicate, therefore, only the state has a bur-
den of persuasion regarding a self-defense claim: it must
disprove the claim beyond a reasonable doubt.
   ‘‘It is well settled that under § 53a-19 (a), a person
may justifiably use deadly physical force in self-defense
only if he reasonably believes both that (1) his attacker
is using or about to use deadly physical force against
him, or is inflicting or about to inflict great bodily harm,
and (2) that deadly physical force is necessary to repel
such attack. . . . We repeatedly have indicated that
the test a jury must apply in analyzing the second
requirement, i.e., that the defendant reasonably
believed that deadly force, as opposed to some lesser
degree of force, was necessary to repel the victim’s
alleged attack, is a subjective-objective one. The jury
must view the situation from the perspective of the
defendant. Section 53a-19 (a) requires, however, that
the defendant’s belief ultimately must be found to be
reasonable. . . .
  ‘‘The subjective-objective inquiry into the defendant’s
belief regarding the necessary degree of force requires
that the jury make two separate affirmative determina-
tions in order for the defendant’s claim of self-defense
to succeed. First, the jury must determine whether, on
the basis of all of the evidence presented, the defendant
in fact had believed that he had needed to use deadly
physical force, as opposed to some lesser degree of
force, in order to repel the victim’s alleged attack. . . .
If the jury determines that the defendant had not
believed that he had needed to employ deadly physical
force to repel the victim’s attack, the jury’s inquiry ends,
and the defendant’s self-defense claim must fail. If, how-
ever, the jury determines that the defendant in fact had
believed that the use of deadly force was necessary,
the jury must make a further determination as to
whether that belief was reasonable, from the perspec-
tive of a reasonable person in the defendant’s circum-
stances. . . . Thus, if a jury determines that the
defendant’s honest belief that he had needed to use
deadly force, instead of some lesser degree of force,
was not a reasonable belief, the defendant is not entitled
to the protection of § 53a-19.’’10 (Citations omitted;
emphasis omitted; footnotes omitted; internal quotation
marks omitted.) State v. Clark, supra, 264 Conn. 730–32.
  We conclude that the jury instructions’ use of the
terms ‘‘honest’’ and ‘‘sincere’’ to describe the nature of
the subjective belief required by the defendant are an
accurate statement of the law that are not likely to
mislead jurors. As the state accurately notes, the well
established usage of these terms in our case law is
consistent with the requirement that the ‘‘defendant
in fact . . . believed that the use of deadly force was
necessary,’’ before determining ‘‘whether that belief
was reasonable, from the perspective of a reasonable
person in the defendant’s circumstances.’’ (Emphasis
omitted; internal quotation marks omitted.) State v.
Clark, supra, 264 Conn. 732; see also, e.g., State v. Saun-
ders, 267 Conn. 363, 373–74, 838 A.2d 186, cert. denied,
541 U.S. 1036, 124 S. Ct. 2113, 158 L. Ed. 2d 722 (2004);
State v. Lemoine, 256 Conn. 193, 207, 770 A.2d 491
(2001); State v. Prioleau, supra, 235 Conn. 286–87.
   The common usages of the word ‘‘actual,’’ ‘‘honest,’’
and ‘‘sincere’’ in this context are consistent with the
subjective aspect of the subjective-objective test pre-
cluding the use of self-defense as a post hoc rationaliza-
tion for otherwise criminal conduct. See Merriam-
Webster’s Collegiate Dictionary (11th Ed. 2003) (defin-
ing ‘‘actual’’ as ‘‘existing in fact or reality,’’ defining
‘‘honest’’ as ‘‘legitimate, truthful’’ or ‘‘genuine, real,’’ and
defining ‘‘sincere’’ as ‘‘honest’’ or ‘‘true’’). Indeed, even
assuming that ‘‘the word actual would be preferred to
the use of the word honest’’ as a matter of draftsman-
ship, the use of the word honest ‘‘did not impose some
higher standard of belief in this case, but only required
a finding that the appellant really believed that he was
in immediate danger. This is a fair statement of the law
of self-defense.’’ United States v. Hardin, supra, 443
F.2d 739. Accordingly, we conclude that the jury instruc-
tions on this point were an accurate statement of the
law that did not mislead the jury.
                            II
   We next turn to the parties’ various claims with
respect to the combat by agreement disqualification to
the justification of self-defense under § 53a-19 (c) (3),
which require us to determine whether: (1) a defendant
is completely disqualified from claiming self-defense
after the state proves combat by agreement, even if the
victim had violated the agreement’s terms by escalating
the use of force beyond what was originally agreed
upon; (2) the trial court improperly charged the jury
that the defendant was required to ‘‘actually know,’’
rather than ‘‘actually and reasonably believe,’’ that the
victim had escalated the fistfight from the ‘‘mere use
of physical force to actual use or imminent use of deadly
force’’; and (3) the trial court’s instructions properly
reflected the applicable burden of proof.11
                            A
   We begin with the state’s alternative ground for
affirmance, which responds to the defendant’s chal-
lenges to the jury instructions on § 53a-19 (c) (3) by
arguing that a finding of illegal combat by agreement
completely disqualifies a defendant from claiming that
his conduct was justified because he acted in self-
defense. Specifically, the state argues that any instruc-
tional error ‘‘could not have harmed the defendant
because it was beneficial to her. Because our statute
makes clear that there is no exception to the combat
by agreement disqualifier, upon the jury’s finding of a
combat by agreement, self-defense becomes inapplica-
ble,’’ despite the fact that the victim may have ‘‘violated
the terms of the agreement and escalated the level of
force beyond what the two had agreed upon . . . .’’ In
response, the defendant cites, for example, Huber v.
United States, 259 F. 766 (9th Cir. 1919), and Grant
v. State, 120 Ga. App. 244, 170 S.E.2d 55 (1969), and
contends, inter alia, that the state’s argument misstates
the law of combat by agreement because it is well
established at common law that the requisite agreement
must be for mutual combat on ‘‘equal terms.’’ (Internal
quotation marks omitted.) We agree with the defen-
dant’s reading of § 53a-19 (c) (3), and conclude that the
trial court’s jury instructions on the topic of combat by
agreement properly reflected the common-law principle
that the requisite agreement does not exist when one
party unilaterally and dangerously escalates the pre-
viously equal terms of a fight.
   Because this issue presents a question of statutory
interpretation, which ‘‘is a question of law, our review
is de novo. . . . When construing a statute, [o]ur funda-
mental objective is to ascertain and give effect to the
apparent intent of the legislature. . . . In other words,
we seek to determine, in a reasoned manner, the mean-
ing of the statutory language as applied to the facts
of [the] case, including the question of whether the
language actually does apply. . . . In seeking to deter-
mine that meaning, General Statutes § 1-2z directs us
first to consider the text of the statute itself and its
relationship to other statutes. If, after examining such
text and considering such relationship, the meaning of
such text is plain and unambiguous and does not yield
absurd or unworkable results, extratextual evidence of
the meaning of the statute shall not be considered. . . .
The test to determine ambiguity is whether the statute,
when read in context, is susceptible to more than one
reasonable interpretation. . . . When a statute is not
plain and unambiguous, we also look for interpretive
guidance to the legislative history and circumstances
surrounding its enactment, to the legislative policy it
was designed to implement, and to its relationship to
existing legislation and common law principles govern-
ing the same general subject matter . . . .’’ (Internal
quotation marks omitted.) State v. Buckland, 313 Conn.
205, 224, 96 A.3d 1163 (2014), cert. denied,     U.S. ,
135 S. Ct. 992, 190 L. Ed. 2d 837 (2015).
   We conclude at the outset that § 53a-19 (c) (3) is
ambiguous, thus permitting resort to extratextual evi-
dence in accordance with § 1-2z. Specifically, the state’s
reading of the language of § 53a-19 (c) (3) is reason-
able—at least facially—insofar as there is a plausible
policy reason for denying those who enter into fights
a right to claim self-defense. We also, however, find
reasonable the defendant’s reading of the statute, which
would permit the use of reasonable force in self-defense
when a fight escalates beyond a previously agreed-upon
level, because that interpretation relies upon the term
‘‘agreement’’ as embodying some mutual consent to the
level of force involved in the encounter. Moreover, the
state’s facially plausible reading of the statute has the
bizarre result of privileging an initial aggressor with
some right of self-defense under subdivision (2) of sub-
section (c), while depriving the mutual combatant
under subdivision (3) of subsection (c) of any right of
self-defense—even when his opponent brings a gun to
an agreed upon fistfight. Accordingly, we look beyond
the text of the statute.
  We begin by reviewing some background principles
concerning combat by agreement under Connecticut
law. Combat by agreement, often referred to as ‘‘mutual
combat,’’ is an exception that operates as a statutory
disqualification from the justification defense of self-
defense. ‘‘A jury instruction regarding the combat by
agreement exception to self-defense is warranted when
the evidence is sufficient to support a reasonable infer-
ence that such a mutual combat occurred.’’ (Internal
quotation marks omitted.) State v. Montanez, 277 Conn.
735, 747, 894 A.2d 928 (2006). ‘‘The agreement required
by . . . § 53a-19 (c) (3) need not be formal or express.’’
State v. Silveira, 198 Conn. 454, 471, 503 A.2d 599 (1986).
Such an agreement may be tacit and inferred from the
facts and circumstances of the case. See State v. Mon-
tanez, supra, 747–48 (sufficient evidence to warrant
combat by agreement instruction when friend urged
one brother to fight with defendant, who returned with
his brother and challenged defendant’s friend to fight
‘‘man-to-man’’); State v. Silveira, supra, 471 (sufficient
evidence to warrant combat by agreement instruction
when defendant and his friends had gone to bar ‘‘to
assist friends who they had heard were in trouble,’’
then ‘‘became embroiled in an altercation’’ with another
person, who ‘‘entered the bar and returned shortly with
companions of his own,’’ who ‘‘converge[d] on the
defendant’s group, with the resulting acceleration of
hostilities’’); State v. Johnson, 53 Conn. App. 476, 481–
82, 733 A.2d 852 (sufficient evidence to justify instruc-
tion on combat by agreement when victim and
defendant ‘‘argued, displayed their weapons, walked to
the middle of the street armed and angry and confronted
each other’’ before ‘‘defendant fired three shots that
killed the victim’’), cert. denied, 249 Conn. 929, 733 A.2d
849 (1999).
   Our cases have not, however, considered the requisite
mutuality of the terms of the combat by agreement,
or, put differently, the legal effect of an altercation
escalating beyond its apparently agreed upon terms.
Stated another way, the question arising in the present
case is whether combat by agreement exists, as a matter
of law, when the parties to an altercation purport to
agree to a fair fistfight, and one party breaches that
agreement by, for example, introducing a deadly
weapon. In addressing this lacuna,12 we note that
although our Penal Code lacks specific commentary on
this point, the drafters of § 53a-19 emphasized that the
justification defenses generally ‘‘attempt to restate the
common law.’’ Commission to Revise the Criminal Stat-
utes, Connecticut Penal Code Comments (1972) p. 7.
Indeed, this court has previously noted that ‘‘[t]he stat-
utes which enumerate the situations where the use of
force is justified’’ should ‘‘ ‘be read in the light of their
common law background, and the fact that an individual
section does not fully state the relevant common law
rule, with all [of] its possible applications, exceptions,
or implications, should not prevent a court from reading
it as incorporating the full body of common law rules
relevant thereto.’ ’’13 State v. Terwilliger, 314 Conn. 618,
654, 104 A.3d 638 (2014), quoting Commission to Revise
the Criminal Statutes, Connecticut Penal Code Com-
ments, supra, p. 7. Our review of sister jurisdictions’
case law and scholarly commentary on this topic dem-
onstrates that the state’s interpretation of § 53a-19 (c)
(3) contravenes the drafters’ expressed intent because it
is wholly inconsistent with the common-law principles
that underlie the statute.14
  As with contracts generally, the common-law analyti-
cal key to combat by agreement is mutual consent. As
Professor Paul Robinson notes in his landmark treatise,
statutory provisions that ‘‘deny a defensive force justifi-
cation to both parties engaged in unauthorized mutual
combat’’ are ‘‘analogous’’ to those under which ‘‘the
threatened harm not be consented to by the actor.’’15 2
P. Robinson, Criminal Law Defenses (1984) § 132, p.
98. Professor Robinson describes mutual combat provi-
sions as a ‘‘response to the evidentiary problems of
determining who the initial aggressor was in such cases,
a fact that can, in some jurisdictions, determine which
participant will be given a defense.’’ Id. He describes
such provisions as potentially ‘‘unnecessary,’’ insofar as
actors engaged in ‘‘mutual combat both are employing
aggressive, rather than defensive force, and neither
actor’s conduct is necessary to his defense and is, for
that reason, unjustified.’’ Id., pp. 98–99. This suggests
then, that there simply is no agreement to engage in
mutual combat when one party escalates the fight
beyond that which the parties had contemplated.
   Consistent with Professor Robinson’s view of combat
by agreement, we agree with the South Carolina
Supreme Court that combat by agreement exists only
when there is a ‘‘mutual agreement to fight on equal
terms for purposes other than protection,’’ because that
equality ‘‘is inherently inconsistent with the concept of
self-defense, and directly conflicts with the ‘no fault’
finding necessary to establish self-defense.’’ (Emphasis
added.) State v. Taylor, 356 S.C. 227, 234, 589 S.E.2d 1
(2003). Thus, the court held that there was insufficient
evidence to justify a mutual combat charge when there
was, in addition to no evidence of ‘‘pre-existing ill-will
or dispute’’ between the victim and the defendant, also
no evidence that the parties knew that each other were
armed. Id. Similarly, the Georgia courts have held that
‘‘[m]utual combat usually arises when the parties are
armed with deadly weapons and mutually agree or
intend to fight with them. Mutual combat does not mean
a mere [fistfight] or scuffle.’’ Grant v. State, supra, 120
Ga. App. 244; see also Huber v. United States, supra, 259
F. 771 (improper to instruct jury that ‘‘if one willingly
entered into a mutual combat with another, without
any intent to do great bodily harm, and thereupon his
adversary resorted to a deadly weapon and was about
to assault him therewith, he would not have the right
to defend himself or resort to such a weapon in his
necessary self-defense’’ [internal quotation marks omit-
ted]); Eckhardt v. People, 126 Colo. 18, 25, 247 P.2d 673
(1952) (‘‘Ordinarily the defense of self-defense in strictly
mutual combat is not allowable, but a limitation on the
right of self-defense does not arise alone from the fact
that the two parties here were mutually engaged in a
fistfight. An agreement to combat and finish their trou-
bles must exist and must be in the nature of an anteced-
ent agreement to so fight.’’); Flowers v. State, 146 Ga.
App. 692, 247 S.E.2d 217 (1978) (improper to charge on
mutual combat when evidence was that defendant and
victim ‘‘had been engaged in a game they called ‘mercy’;
the game was a simple showdown of strength where
each man tried to out-grip the other’s hand,’’ which
devolved into fistfight and ultimately guns were pro-
duced, insofar as ‘‘there is no evidence showing that
these men agreed to fight with weapons’’); accord State
v. Crisantos, 102 N.J. 265, 274, 508 A.2d 167 (1986)
(noting that mutual combat, for purposes of reducing
murder to manslaughter at common law, requires that
‘‘the contest must have been waged on equal terms and
no unfair advantage taken of the deceased’’ [internal
quotation marks omitted]).
   In light of the persuasive logic of these authorities, we
conclude that the combat by agreement disqualification
under § 53a-19 (c) (3) did not preclude the defendant
from relying on the justification of self-defense as a
matter of law. In our view, the state’s arguments to the
contrary foster the illogical and dangerous result of
depriving a participant in a supposedly fair fistfight of
the right to self-defense when his or her opponent
shows up with a deadly weapon, an unexpected gang
of supporters, or an unexpected gang of supporters
wielding deadly weapons. In contrast, we view the
instruction given by the trial court as consistent with
the well established common-law principle requiring
mutual consent as to the terms of engagement, notwith-
standing the fact that those terms might lack the accep-
tance and pedigree of those sponsored by the Ninth
Marquess of Queensbury.16 Put differently, an escalation
in the encounter beyond a fistfight meant that there
was, in essence, no agreement at all. Accordingly, we
disagree with the state’s argument that the defendant’s
intention to have a ‘‘fair one’’ with the victim, without
weapons or other friends participating,17 constituted
combat by agreement that disqualified her as a matter
of law pursuant to § 53a-19 (c) (3) from claiming self-
defense in the instance the fight escalated beyond the
agreed upon terms.18
                             B
   We now turn to the defendant’s first challenge to the
portion of the jury instruction charging the jury on
combat by agreement, namely, that the trial court
improperly charged that the defendant was required to
‘‘actually know,’’ rather than ‘‘actually and reasonably
believe,’’ that the victim had escalated the fistfight from
the ‘‘mere use of physical force to actual use or immi-
nent use of deadly force . . . .’’ The defendant con-
tends that this instruction was improper because a
defendant is required only to have a ‘‘reasonable belief’’
that the other party escalated the confrontation, rather
than actual knowledge, and argues that State v. Abra-
ham, 84 Conn. App. 551, 557–58, 854 A.2d 89, cert.
denied, 271 Conn. 938, 861 A.2d 514 (2004), which the
Criminal Jury Instructions Committee cited as authority
for that pattern charge, does not support that portion
of the instruction. In response, the state argues, inter
alia, that under State v. Silveira, supra, 198 Conn. 454,
‘‘the self-defense disqualifiers in § 53a-19 (c) are [not]
assessed from the defendant’s perspective and his rea-
sonable beliefs.’’ We agree with the state, and conclude
that the jury instructions did not misstate the law gov-
erning combat by agreement.
   In Silveira, this court concluded that the proviso in
§ 53a-19 (a) makes ‘‘subsection (a) expressly subject to
subsections (b) and (c),’’ meaning that the legislature
made plain and unambiguous ‘‘its intent that the use of
force in self-defense or defense of another, as provided
in subsection (a), is not justified where a defendant has
engaged in the conduct described in subsection (c). The
issue under subsection (c) is not whether the defendant
reasonably believed that he provoked the use of force,
or that he was the initial aggressor, or that there existed
an agreement to engage in combat. The issue, rather,
is whether the defendant did provoke the use of force,
or was the initial aggressor, or did agree to engage in
combat. The trial court did not err in refusing to instruct
that the exceptions of provocation, aggression and com-
bat by agreement must be considered from the perspec-
tive of the defendant.’’ (Emphasis altered.) State v.
Silveira, supra, 198 Conn. 470; see also id., 469 (‘‘by
the terms of the statute, the use of force in self-defense
or defense of another is never justified where the condi-
tions set forth in subsection [c] [of § 53a-19] are found
to exist’’).
   We conclude that the trial court’s instruction, requir-
ing the defendant to ‘‘[know] of such a violation’’ of the
terms of the mutual combat agreement, is a correct
statement of the law. Although the defendant accurately
observes that the pattern instruction on which it was
based is not doctrinally supported by State v. Abraham,
supra, 84 Conn. App. 558; see also footnote 12 of this
opinion; the charge nevertheless is consistent with State
v. Silveira, supra, 198 Conn. 470, which requires the
jury to decide what actually happened, rather than what
the defendant reasonably might have perceived what
happened. Second, it is consistent with the overarching
subjective-objective standard by which self-defense
claims are determined, under which objective reason-
ableness is considered only if the defendant himself
perceived the need for self-defense at the time of the
altercation. See, e.g., State v. Clark, supra, 264 Conn.
730–32. Accordingly, we conclude that the trial court’s
instruction on this point did not misstate the law of
self-defense.
                            C
  Finally, we turn to the defendant’s claim that the jury
instructions did not place the correct burden of proof
on the state with respect to the proof of the statutory
disqualifier of combat by agreement, in particular by
(1) shifting the burden of proof to the defense, and (2)
failing to direct the jury that the state retained the
burden of disproving self-defense or proving combat
by agreement by a reasonable doubt.19 In response, the
state contends that read in their entirety, the trial court’s
jury instructions properly informed the jury of the
state’s burden of proof. We agree with the state, and
conclude that the trial court’s self-defense charge did
not misstate the burden of proof.
   Viewing the charge in its entirety, as we must; see,
e.g., State v. Lavigne, supra, 307 Conn. 599–600; we
conclude that the instructions properly stated the bur-
den of proof, both as to self-defense generally and with
respect to the combat by agreement statutory disquali-
fier specifically. The trial court repeatedly reminded
the jury that: (1) the state bore the burden of disproving
self-defense beyond a reasonable doubt as a general
matter; (2) the state bore the burden of proving the
statutory disqualifiers, including combat by agreement
and retreat; and (3) the defendant had no burden of
proof at all. Contrary to the defendant’s arguments, we
conclude that the jury charge properly articulated the
state’s burden of proof with respect to self-defense gen-
erally, and combat by agreement specifically. See, e.g.,
State v. Clark, supra, 264 Conn. 730–31.
      The judgment is affirmed.
  In this opinion ROGERS, C. J., and PALMER,
ZARELLA, EVELEIGH and McDONALD, Js., concurred.
  1
     General Statutes § 53a-19 provides in relevant part: ‘‘(a) Except as pro-
vided in subsections (b) and (c) of this section, a person is justified in using
reasonable physical force upon another person to defend himself or a third
person from what he reasonably believes to be the use or imminent use of
physical force, and he may use such degree of force which he reasonably
believes to be necessary for such purpose; except that deadly physical force
may not be used unless the actor reasonably believes that such other person
is (1) using or about to use deadly physical force, or (2) inflicting or about
to inflict great bodily harm.
   ‘‘(b) Notwithstanding the provisions of subsection (a) of this section, a
person is not justified in using deadly physical force upon another person
if he or she knows that he or she can avoid the necessity of using such
force with complete safety (1) by retreating, except that the actor shall not
be required to retreat if he or she is in his or her dwelling, as defined in
section 53a-100, or place of work and was not the initial aggressor . . . .
   ‘‘(c) Notwithstanding the provisions of subsection (a) of this section, a
person is not justified in using physical force when (1) with intent to cause
physical injury or death to another person, he provokes the use of physical
force by such other person, or (2) he is the initial aggressor, except that
his use of physical force upon another person under such circumstances is
justifiable if he withdraws from the encounter and effectively communicates
to such other person his intent to do so, but such other person notwithstand-
ing continues or threatens the use of physical force, or (3) the physical
force involved was the product of a combat by agreement not specifically
authorized by law.’’
   Although this statute has been amended by our legislature since the
events giving rise to this appeal; see Public Acts 2010, No. 10-36, § 15; that
amendment has no bearing on the merits of the present case. Accordingly,
for the sake of simplicity, we refer to the current revision of the statute.
   2
     The defendant appealed from the judgment of the trial court to the
Appellate Court. Thereafter, we granted the defendant’s motion to transfer
the appeal to this court in accordance with General Statutes § 51-199 (c)
and Practice Book § 65-2.
   3
     At trial, the defendant and the state presented two different versions of
the events that led to this appeal. The defendant claimed that the victim,
without provocation, simply attacked her and that she had reacted in self-
defense. The state, however, contended that the defendant and the victim
had engaged in an illegal combat by agreement. To provide greater context
for what the jury was required to determine at trial, evidence in support of
the defendant’s version of events is set forth in the footnotes of this opinion.
   4
     The defendant testified that she had helped the victim by doing things
such as giving her food and driving her places. The victim, however, had
been saying negative things about the defendant and the defendant knew
that the victim had a reputation for violence. In the period leading up to
the Memorial Day weekend of 2010, the defendant had stopped associating
with the victim.
   5
     The defendant testified that after Kennedy came outside and other people
came downstairs from the victim’s apartment, James Turner, another resi-
dent, advised the defendant to leave, saying it was not safe for her to stay
there. The defendant further testified that the victim and her family had
blocked the entrance to the building so the defendant could not get to her
apartment. The defendant was scared and Murdock’s aggression toward her
caused her to have flashbacks to physical abuse she had suffered at the
hands of her former husband. She left and walked around the corner to
the home of her cousin, Tiny Lester, where she explained to Lester what
was happening.
   Lester then offered to help the defendant get into her apartment because
the defendant’s children and goddaughter were there, and the defendant
feared for their safety. Because Lester knew the victim’s family, the defen-
dant hoped that Lester would be able to calm them down and that she
would be able to get into her apartment safely. Lester and the defendant
walked back to the defendant’s building.
   When they arrived in front of the building, Lester and the defendant
stopped outside the gate in front, and Lester said, ‘‘she don’t got time for
this; let her go upstairs; there’s kids in this house; let her go upstairs; she
don’t got time for this.’’ The altercation between the victim and the defendant
happened shortly thereafter.
   6
     Testimony offered at trial by some of the state’s witnesses established
that the defendant and the victim understood a ‘‘fair one’’ to be a fair fight
between the parties involved in the dispute, involving only those two people
and with no assistance from other individuals and no weapons—just fists
and feet.
   7
     More specifically, the defendant testified that one of the victim’s cousins
had handed a lime green object to the victim. The victim then said that she
was going to attack the defendant, and charged toward her.
   The defendant testified that, as the victim approached, the defendant
realized that the lime green object in the victim’s hand was sharp, and raised
her hands up to cover her face. The defendant then drew the small, two
inch steak knife in self-defense. The defendant testified that the victim
swung first, slashing downward at the defendant with the lime green object,
but missing because the defendant stumbled backward. The victim moved
so quickly that the defendant could not get away. Out of fear, the defendant
closed her eyes and swung with the steak knife in her hand in order to try
to protect herself. She did not realize that she had cut the victim until she
heard the victim shout that she was cut.
   8
     The defendant testified that she was nervous and froze, and originally
denied that she had cut the victim because she was scared and did not
realize that the law allowed her to protect herself. The defendant then tossed
the knife under a nearby vehicle. One witness, James Turner, testified that
the whole altercation could not have lasted more than four seconds.
   The defendant further testified that, when the victim came back outside
to go to the hospital, the defendant did not see any blood on the victim and
only knew that the victim had been cut. The defendant’s cell phone was
not charged so she was unable to call 911 to explain that she had just been
attacked by the victim. Instead, she approached Atkins, who was on the
telephone with the 911 dispatcher, and told her: ‘‘[M]ake sure you tell the
cops that you guys came to jump me.’’ As soon as the police arrived, the
defendant approached an officer to explain what had happened.
   9
     We note that the following portions of the self-defense instruction pro-
vided by the court are relevant to this claim on appeal: ‘‘The [test] you are
to apply is a subjective objective test, meaning that it has some subjective
aspects and some objective aspects. You must consider the situation from
the perspective of the defendant; that is, what did the defendant actually
believe as best as can be inferred from the evidence. This is the subjective
aspect of the test. . . .
   ‘‘The first question you must ask is simply as a matter of fact whether
the defendant actually, that is honestly and sincerely, entertained the belief
in question when she acted as she did. . . . A defendant cannot justifiably
act on her actual belief however honestly or sincerely she held it if that
belief would not have been shared by a reasonable person in our circum-
stances viewing those circumstances from the defendant’s point of view.
   ‘‘[T]he defense of self-defense has four elements. One, that the defendant
actually believed that someone was using or was about to use physical force
against her. If you find that the force used by the defendant was deadly
physical force, then this element requires that the defendant actually believed
that the other person was, A, using or about to use deadly physical force
against her or, B, was inflicting or about to inflict great bodily harm upon
her. . . .
   ‘‘Element three, that the defendant actually believed that the degree of
force she used was necessary to repel the attack. Again, if you find that
that force used by the defendant was deadly physical force, then this element
requires that the defendant actually believed that deadly physical force was
necessary to repel the attack. . . .
   ‘‘Now, I’ll go over these elements again in detail from that perspective.
The first element is that when the defendant used offensive force against
[the victim] she actually, that is honestly and sincerely, believed that the
other person was using or about to use physical force against her. . . .
   ‘‘If you have found that the force used by the defendant was deadly
physical force, then you must find the defendant actually believed that [the
victim] was not only using or about the use physical force upon her but
that the other person, namely [the victim] . . . was either using or about
to use deadly physical force against the defendant or inflicting or about to
inflict great bodily harm upon her. . . .
   ‘‘The act of [the victim] leading to the defendant’s use of defensive physical
force may not be [an] actual threat . . . or an actual assault. The test is
not what the other person actually intended but what the other person’s
act caused the defendant to believe was the intention of the other. In other
words, the danger to which the defendant was reacting may not have been
. . . actual or real. In judging a danger to herself, the defendant is not
required to act with infallible judgment. A person acting in self-defense is
sometimes required to act instantly and without time to deliberate and
investigate. Under some circumstances, it is possible . . . to perceive an
actual threat when none, in fact, existed. . . .
   ‘‘The third element is that when the defendant used physical force upon
[the victim] for the purposes of defending herself she actually, that is honestly
and sincerely, believed that the degree of force she used was necessary for
that purpose. And this applies whether you have found that the defendant
used deadly physical force or not. The question is whether the defendant
believed that it was necessary to use the degree of force that she used to
defend herself from the attack.’’ (Emphasis added.)
   10
      For a comprehensive doctrinal explanation of justification defenses
such as self-defense, see State v. Singleton, 292 Conn. 734, 746–49, 974 A.2d
679 (2009), and State v. Montanez, 277 Conn. 735, 752–53, 894 A.2d 928 (2006).
   11
      We note that, with respect to combat by agreement, the trial court
charged the jury that ‘‘another circumstance under which a person is not
justified in using any degree of physical force in self-defense against another
is when the physical force is the product of an illegal combat by agreement.
Under this provision, it is not necessary that there be a formal agreement.
Such agreement may be inferred from the conduct of the parties. To infer
such an agreement, you must look at all the circumstances leading up to
and preceding the event in question as well as all of the circumstances
surrounding this event itself based on the entire evidence presented in your
own credibility assessments. This exception would not apply despite an
agreement for mutual combat if you find that the terms were violated by
[the victim] and that her conduct [toward] the defendant was in violation
of their agreement. And further, that the defendant knew of such a violation.
Violation means that [the victim’s] use of force exceeded the terms of the
agreement with the defendant and that it escalated beyond what they had
then agreed to as . . . to either the extent or form of . . . combat.
   ‘‘It is important to remember that the defendant has no burden of proof
to prove that her use of physical force was not the product of a combat by
agreement. To the contrary, you may only reject her defense on the basis
of the statutory disqualification if you find that the state . . . has proved
beyond a reasonable doubt that the defendant and . . . [the victim] had
engaged in . . . combat by agreement.’’ (Emphasis added.)
   We note that this instruction mirrors the pattern jury instruction promul-
gated by the Criminal Jury Instructions Committee, which is published on
the Judicial Branch website. See Connecticut Criminal Jury Instructions
(4th Ed. 2011) § 2.8-2 (C), available at http://www.jud.ct.gov/JI/criminal/
part2/2.8-2.htm (last visited September 1, 2015).
   For the challenged portion of the instruction pertaining to the burden of
proof, see footnote 19 of this opinion.
   12
      The Criminal Jury Instructions Committee cited the Appellate Court’s
decision in State v. Abraham, 84 Conn. App. 551, 854 A.2d 89, cert. denied,
271 Conn. 938, 861 A.2d 514 (2004), as authority for the pattern jury instruc-
tion utilized by the trial court in this case. The Appellate Court’s opinion
in Abraham recited, but did not address the legal accuracy of, the challenged
instruction on this particular point and, therefore, is of minimal persuasive
value in the present appeal. See id., 559–60 (considering whether sufficient
evidence of combat by agreement existed when defendant claimed that he
was mere bystander who had intervened in defense of another person).
   13
      To this end, we note that § 53a-19, like much of our state’s Penal Code,
is modeled heavily after coordinate provisions of New York’s Penal Code;
although principles stated in the Model Penal Code are also informative in
its interpretation. See, e.g., State v. Pond, 315 Conn. 451, 483, 108 A.3d 1083
(2015). The parties do not cite, and our independent research did not reveal,
any on point New York cases under that state’s identical combat by
agreement statute. N.Y. Penal Law § 35.15 (McKinney 2009).
   14
      The concurring justice criticizes our reliance on common-law principles
to resolve this ambiguity as ‘‘inconsistent’’ with State v. Singleton, 292 Conn.
734, 974 A.2d 679 (2009), asking rhetorically how we ‘‘can use common-law
principles to find an exception not explicitly written in this provision of the
same statute when a party to a combat by agreement escalates the level
of violence.’’ As the concurrence accurately points out, in Singleton, we
disagreed with a defendant’s claim that the trial court had improperly failed
to instruct the jury that ‘‘the initial aggressor using nondeadly force who is
met with deadly force by the victim may be justified in using deadly force
to repel the victim.’’ Id., 764. We held that the defendant’s argument was
inconsistent with the ‘‘plain and unambiguous’’ language of § 53a-19 (c) (2),
which ‘‘provides that the initial aggressor is justified in using physical force
only if he withdraws from the encounter and certain other conditions are
satisfied. It does not provide, or suggest, that an initial aggressor who
uses nondeadly force is justified in using deadly force to repel the victim’s
unlawful escalation of force to the deadly level.’’ (Emphasis added.) Id.,
765. Our resort to common-law principles in this case is not inconsistent with
Singleton, because that case concerned plain and unambiguous statutory
language. In contrast, the present case presents statutory language that a
majority of this court deems ambiguous as to the meaning of the term
‘‘agreement’’ under § 53a-19 (c) (3), rendering appropriate resort to common-
law principles to resolve that ambiguity in accordance with the drafters’
intent. See General Statutes § 1-2z.
   15
      The American Law Institute followed this consent approach in drafting
the Model Penal Code, which lacks an express combat by agreement provi-
sion. The commentary to the Model Penal Code notes that it ‘‘accomplished’’
that same principle insofar as it ‘‘allows forceful responses only to ‘unlawful
force’ and defines that term . . . not to include force to which the recipient
has consented.’’ 1 A.L.I., Model Penal Code and Commentaries (1985) § 3.04,
comment 3 (c), p. 47; see also id., § 3.11, p. 156 (‘‘ ‘unlawful force’ means
force, including confinement, that is employed without the consent of the
person against whom it is directed’’). The commentary observes that the
‘‘question of consent presents a problem of some difficulty. It is desirable,
on the one hand, to exclude from the range of protective force, especially
of force employed for the protection of another, most cases in which the
person sought to be protected has in fact consented, whether or not the
law would otherwise give legal effect to the consent. Thus A and B may
agree to fight under such conditions that they both are guilty of a crime
and such that, according to some decisions, they have cross actions for
battery against each other, their consent being denied legal effect.’’ Id.,
§ 3.11, comment 1, pp. 157–58.
   16
      The Queensbury Rules were a ‘‘code of rules that most directly influ-
enced modern boxing. Written by John Graham Chambers, a member of
the British Amateur Athletic Club, the rules were first published in 1867
under the sponsorship of John Sholto Douglas, ninth marquess of Queens-
berry, from whom they take their name.’’ Encylopaedia Brittanica, ‘‘Marquess
of Queensbury Rules,’’ (2015), available at http://www.britannica.com/
sports/Marquess-of-Queensberry-Rules (last visited September 1, 2015).
   17
      See footnote 6 of this opinion.
   18
      The concurrence also posits that, because ‘‘fights develop without
advanced planning, and that we can find combat by agreement even without
any express agreement to fight, it seems unlikely that the parties would
establish specific terms, including the level of force to be used, prior to the
commencement of the fight.’’ We disagree with the concurrence’s reliance
on this speculative generalization, and instead emphasize that the existence
of an agreement to fight, including any limitations on the type or amount
of force permissible and the breach of those limitations, is a question of
fact for the trier. See, e.g., State v. Montanez, supra, 277 Conn. 747–48.
   19
      We note that the trial court directed the jury generally that the ‘‘state
must not only prove beyond a reasonable doubt all of the elements of the
crime charged in order to obtain a conviction, but must also disprove beyond
a reasonable doubt that the defendant acted in self-defense. If the state fails
to disprove beyond a reasonable doubt the defendant acted in self-defense,
you must find the defendant not guilty despite the fact that you have found
the elements of the crime proved beyond a reasonable doubt. The defendant
has no burden of proof whatsoever [with] respect to this defense.’’ After
discussing the substantive elements of self-defense, the trial court again
reminded the jury ‘‘that the defendant has no burden of proof regarding any
of these elements. Instead, the state bears the sole and exclusive burden
of proving beyond a reasonable doubt that the defendant did not act in self-
defense . . . a burden that it can meet by disproving at least one of these
elements beyond a reasonable doubt.’’
   The trial court then repeated those burdens with respect to the statutory
disqualifications, stating that ‘‘the state can defeat the defendant’s claim of
self-defense by proving one of the statutory disqualifications to the use of
deadly physical force,’’ including retreat and combat by agreement, and
again emphasizing that the defendant ‘‘has no burden [of proof] whatsoever’’
with respect to either retreat or combat by agreement.
   With respect to combat by agreement, after explaining the elements, the
trial court instructed the jury that ‘‘[i]t is important to remember that the
defendant has no burden of proof to prove that her use of physical force
was not the product of a combat by agreement. To the contrary, you may
only reject her defense on the basis of the statutory disqualification if you
find that the state has proved . . . beyond a reasonable doubt that the
defendant and [the victim] had engaged in . . . combat by agreement.
   ‘‘I said this several times but it bears repeat[ing]. You must remember
that the defendant has no burden of proof whatsoever [with] respect to the
defense of self-defense. Instead, it is the state that must prove beyond a
reasonable doubt that the defendant did not act in self-defense if it is to
prevail on its charges of assault in the second degree and criminal attempt
of assault in the first degree. To meet this burden, the state need not disprove
all four of the elements of self-defense. Instead, it can defeat the defense
of self-defense by disproving any one of the four elements of self-defense
beyond a reasonable doubt to your unanimous satisfaction.’’
