*789INTRODUCTION
Under California law, the trial judge in a criminal case must instruct the jury on all lesser-included offenses supported by substantial evidence. Here, defense counsel requested an instruction on the lesser-included offense of involuntary manslaughter-an unlawful killing without malice. Counsel conceded that defendant Tyshaun Vasquez administered a beating that killed Eddie Ray Smith, Jr., but argued that defendant was not subjectively aware his actions could be deadly because Smith had a hidden spinal injury (metal rods had been placed in his neck in a prior surgery), the fatal injury was *790immediately adjacent to the metal rods, and the victim's other injuries were relatively minor. Defendant contends that the trial court should have granted his instructional request because there was substantial evidence to support the instruction and that the error was prejudicial. We agree and reverse the judgment.
PROCEDURAL BACKGROUND
By information filed January 6, 2016, defendant and codefendant Jordan E. were each charged with one count of special-circumstance first degree murder ( Pen. Code,
Trial was by jury. Defendant did not testify. The court denied his request to instruct on involuntary manslaughter as a lesser-included offense of murder but granted his request to instruct on second degree murder. The jury convicted defendant of second degree murder. It acquitted him of first degree murder and attempted robbery and found the special-circumstance allegation not true.
Defendant moved for a new trial, again arguing that the court should have instructed the jury on involuntary manslaughter. The court denied the motion and sentenced defendant to 15 years to life in state prison for count 1. The court awarded him 793 days actual custody credit and 0 days local conduct credit.
Defendant filed a timely notice of appeal.
FACTUAL BACKGROUND
On November 30, 2014, at around 12:30 a.m., defendant and Jordan were hanging out in the skate area of Rancho La Cienega Park in Los Angeles. There, they encountered Smith. According to Angel T., the sole eyewitness at trial, when defendant and Jordan saw Smith, defendant said, "let's go get that guy. Let's see if he got money or jewelry or anything like that stuff." The *79143-year-old Smith was "skinny": 5 feet 10 inches tall and 129 pounds. In contrast, defendant was 19 and "notably" taller and heavier than Smith.
Defendant and Jordan approached Smith and grabbed him. Defendant dug around in Smith's pockets. It is unclear whether he took anything. Jordan and defendant then punched Smith about 15 times, knocking him to the ground. While Smith was on the ground, defendant stomped on his head "and like his whole body pretty much" approximately 20 times. Smith, meanwhile, was yelling for help. As defendant stomped on Smith, Jordan picked up a nearby metal trash can and threw it at Smith, hitting him in the right side of the hip. Eventually, defendant and Jordan left the scene.
Soon after the incident, Joel Williams, then a firefighter with the Los Angeles Fire Department, responded to the scene after being flagged down by a woman in the park. Williams saw that the man on the ground, whom he later identified as Smith, needed medical attention. Williams moved the trash can he found on Smith's body and after performing a standard examination, determined that Smith was dead.
Kevin Young, a medical examiner for the Los Angeles County Department of Medical Examiner-Coroner, performed the autopsy. Young noted a variety of external injuries to Smith's body: trauma on both sides of his head; abrasions on his forehead, temple, and cheek; lacerations on the side of his eye; a swollen right ear with a hematoma and blood and abrasions in front of and behind it; and other injuries. Each of these injuries, considered alone, was nonlethal. All were premortem.
Young also found one significant internal injury: a neck fracture in the C2-C3 vertebrae, just below the jawline. This injury, which can be fatal because it restricts breathing, was likely caused by impact wounds to Smith's head: blunt force trauma was determined to be a "substantial contributing factor" to Smith's death. Young noted that during a prior orthopedic surgery, metal rods had been inserted into Smith's neck directly adjacent to the fracture. That surgery and the rods compromised Smith's neck strength and made him more susceptible to a neck injury in *887the area. Indeed, because the break occurred right at the edge of the metal rod, the rod could have acted as a fulcrum and contributed to the break.
Still, it would take a high-impact event to cause a serious injury to Smith's neck. Getting punched in the neck would "probably not" be enough. In addition, falling or getting punched in the face likely would not have created a high enough impact to fracture Smith's neck. But getting stomped in the head-either once or repeatedly-or being hit with a metal trash can could be enough to cause a fracture. The location of the impact would have affected *792the severity of the injury, since the rods made Smith's neck weaker in some areas, such as at the C2-C3 vertebrae, but did not weaken his neck as much in other areas. And Young testified that Smith did not have any other serious head or neck injuries, such as a fractured skull, tooth damage, intracranial bleeding, or brain bruises.
In the examination, Young also inventoried Smith's personal effects. Smith had 12 cents, a wallet, a social security card, multiple credit cards, and a cell phone, but no jewelry.
DISCUSSION
Defendant contends the trial court's refusal to instruct on involuntary manslaughter as a lesser-included offense to murder was erroneous and prejudicial. The People argue the instruction was not supported by substantial evidence and overwhelming evidence rendered any error harmless. We conclude there was substantial evidence that defendant acted without malice and there is a reasonable probability that he would have obtained a more favorable outcome if the involuntary manslaughter instruction had been given.
1. Instructional Duty and Standard of Review
"California law requires a trial court, sua sponte, to instruct fully on all lesser necessarily included offenses supported by the evidence." ( People v. Breverman (1998)
"In deciding whether evidence is 'substantial' in this context, a court determines only its bare legal sufficiency, not its weight." ( Breverman , supra , 19 Cal.4th at p. 177,
When the defense requests the instruction, the refusal to instruct on a lesser-included offense may also violate the federal constitution's requirement that the courts afford every criminal defendant " 'a meaningful opportunity to *793present a complete defense.' " ( Crane v. Kentucky (1986)
We review de novo the trial court's failure or refusal to instruct on a lesser-included offense. ( People v. Cook (2006)
2. Involuntary manslaughter is a lesser-included offense of murder.
Murder is "the unlawful killing of a human being, or a fetus, with malice aforethought." ( § 187, subd. (a).)
Implied malice has both objective and subjective components. The objective test requires " ' "an act, the natural consequences of which are dangerous to life ...." ' " ( People v. Knoller (2007)
An unlawful killing without malice is involuntary manslaughter. (§ 192; see, e.g., People v. Blakeley (2000)
*794People v. Butler (2010)
*8893. The court denied defendant's requests for an instruction on involuntary manslaughter.
After the prosecution rested, the court held a hearing to discuss jury instructions. Defense counsel asked the court to instruct the jury on involuntary manslaughter based on a lack of malice. Counsel's theory was that if the jury rejected Angel's testimony, it would have to acquit defendant of attempted robbery, felony murder, and the special circumstance. At that point, the only contested issue would be defendant's intent-that is, whether he acted with malice.
Defense counsel explained that in light of "the coroner's testimony that none of the [other] blows were fatal and given the fulcrum of where the neck was broken, there was no intent to kill." Though defendant committed an unlawful act, it was "a freak thing." "Beating someone badly, but not inflicting deadly blows, not knowing that the person had prior ... cervical surgery before, how would anybody know? Again, there's no intent to kill. It's a terrible thing that happened, but if the jury rejects-again, rejects count 2 [attempted robbery] and the permutations of it, you know, we're left with regular murder or manslaughter. And, again, that's a question of fact for the jury to decide, the intent aspect. If there's no intent to kill, it can be nothing but involuntary manslaughter."
The prosecutor responded that "if this were a fistfight, I totally get where counsel is coming from. But someone lying on the ground being stomped on 20 times is evidence that-I don't see how a person is not aware that that behavior can result in death and disregard it, the likelihood of someone dying from that behavior."
The following day, the court issued a written statement of decision denying counsel's request for an involuntary manslaughter instruction. The court made *795various factual findings, including that "defendant stomped approximately 20 times [on] the victim's head and body in a forceful manner." The court then concluded the evidence did not support the instruction because "defendant did not simply start a fistfight in which an unlucky blow resulted in the victim's death. He savagely beat and stomped the victim to death." Because this was felonious conduct, the court declined to give the instruction. (See Breverman , supra , 19 Cal.4th at pp. 162, 177,
Defense counsel urged the court to reconsider its decision. While the court might not have been required to give the instruction sua sponte, counsel argued, it was required to give it upon request. Counsel explained that Smith's broken neck was an anomaly, and "given the facts that none of the injuries, internal or external, described by Dr. Young were fatal or life-threatening, [ ] the perpetrator would not know the natural and probable consequences would be" dangerous to human life. The significance of this evidence was "for the trier of fact to make the determination with regards to malice, to intent."
Indeed, counsel revealed that if the court did give the involuntary manslaughter instruction, he would not even ask the jury to acquit; he would instead ask the jury to convict defendant of involuntary manslaughter. "My client should be held responsible for what he did," counsel explained. "But to say that the jury should not even consider [involuntary manslaughter] because of the nature of the beating, that someone should know that the natural consequences would be dangerous to human life, I don't think that's the situation *890given the type of injuries and based on the coroner's testimony."
Finally, counsel emphasized that "the court is precluding me from arguing a defense that I laid out at the very beginning, during voir dire. I was that confident, given the nature of the injuries."
After hearing further argument, the court again denied counsel's request for the instruction.
4. There was substantial evidence from which the jury could conclude defendant acted without malice.
As discussed, a defendant acts without implied malice if he lacks a subjective awareness that his conduct carries " 'a high degree of probability that it will result in death.' " ( People v. Knoller , supra , 41 Cal.4th at p. 152,
California courts have long recognized that not all beatings are life-threatening. "Normally, hitting a person with the hands or feet does not constitute murder in any degree. [Citations.] But if death ... is a reasonable or probable consequence of the beating the offense may be murder. [Citation.] Thus, to constitute murder there has to be either an intent to kill or such wanton and brutal use of the hands [or feet] without provocation as to indicate that they would cause death ...." ( People v. Teixeira (1955)
Here, there was sufficient evidence from which the jury could have reasonably concluded that the beating defendant administered to Smith was not so wanton and brutal as to demonstrate a conscious disregard for human life. Young, the medical examiner, testified that almost all of Smith's injuries-taken alone-were nonlethal. Smith did not suffer a fractured skull, tooth damage, intracranial bleeding, or brain bruises, which might be expected from multiple high-impact blows to the head. As to Smith's neck specifically, a prior surgery had inserted metal rods into his neck and spine, making Smith vulnerable to a serious neck injury in the precise spot where the break occurred. The weakness of Smith's neck was not visible externally. And Young agreed that since Smith's neck snapped at a point immediately adjacent to the end of the metal rod, the rod could have acted as a fulcrum, thereby increasing the force on that area. A reasonable juror could have inferred from this evidence that the blows were not particularly severe and further inferred that defendant believed beating up Smith would injure him but not kill him.
The People cite two cases in support of their claim that no substantial evidence supported an involuntary manslaughter instruction here. Both are inapt.
In Guillen , the manner and circumstances of a jail assault on a murder victim provided sufficient evidence, under an aiding and abetting theory, to *797support the *891jury's conclusion that each defendant inmate was subjectively aware that the natural and probable consequences of his conduct were dangerous to life. ( People v. Guillen (2014)
Unlike in Guillen , in which the court assessed whether the evidence was sufficient to support the verdict , we must decide whether there was sufficient evidence to warrant an instruction on a lesser-included offense. Thus, whereas Guillen viewed the evidence in the light most favorable to the prosecution, we must view the evidence in the light most favorable to the defense. ( People v. Millbrook , supra , 222 Cal.App.4th at p. 1137,
In Evers , the other case cited by the People, the court concluded there was no error in failing to instruct on involuntary manslaughter where the child victim suffered severe injuries, and evidence of the defendant's prior child abuse established he was aware of the risk of his actions. ( People v. Evers (1992)
In sum, because there was substantial evidence in this case from which a reasonable juror could have doubted that defendant was subjectively aware the beating could kill Smith, the court was required to instruct on the lesser-included offense of involuntary manslaughter.
*7985. The error was prejudicial.
In a non-capital case, the erroneous failure to instruct on a lesser-included offense is typically an error of state law. ( People v. Rogers , supra , 39 Cal.4th at pp. 867-868,
The rationale for requiring courts to instruct on lesser-included offenses is to avoid forcing the jury into an " 'unwarranted all-or-nothing choice' " that creates the risk the jury will convict on the charged offense even though one of the elements remains in doubt because " 'the defendant is plainly guilty of some offense.' " ( People v. Hughes (2002)
Under the instructions given in this case, the jury was forced to choose between convicting defendant of second degree murder and acquitting him entirely. As we shall explain, there is a reasonable probability that the jury chose second degree murder to avoid the more implausible alternative that defendant was not guilty of any crime. Put another way, we hold there is a reasonable probability that at least one juror would have voted to convict defendant of involuntary manslaughter if given the chance.
*7995.1. The instruction embodied the defense theory of the case.
The failure to instruct on a lesser-included offense is more likely to be prejudicial where it strikes at the heart of the defense. ( People v. Neidinger (2006)
Here, counsel structured the entire defense around one element: malice. In his opening statement, counsel explained that defendant, "right or wrong, has a penchant for getting into stupid fights. Okay? Nothing to do with attempted robberies or-just getting into fights all the time." Counsel acknowledged Smith was beaten. But most of Smith's injuries were nonlethal. And, counsel explained, Smith had prior injuries that had compromised the vertebrae in the very spot in which his neck broke. Counsel, therefore, concluded his opening statement by telling the jury, "I would suggest to you that at the end of the day that you're going to find ... that this is in fact an involuntary manslaughter."
The cross-examination of the medical examiner was also structured around malice. For example, counsel asked Young about each of Smith's injuries and confirmed that none of them was potentially fatal. He confirmed Smith's teeth were intact, that his skull was not fractured, and that there was no trauma to his brain. Then, counsel spent the bulk of cross-examination asking Young about the relationship between *893Smith's prior neck injury and his death. Counsel elicited testimony that the break itself was right on the edge of the metal rods, and those rods could have acted as a fulcrum that helped cause the break. As he explained when he requested the instruction, this was the foundation of counsel's theory that defendant acted without conscious disregard for human life.
Yet after asking the jury in his opening statement to convict of involuntary manslaughter, in his closing argument, counsel asked them to acquit entirely. He still conceded the other elements: "There's no issue whether Tyshaun Vasquez was involved in this case. ... That's not an issue here. The issue is a question of was there a crime committed and what is that crime? " And he still focused on intent: did defendant know that death was a natural and probable consequence of his actions?
Counsel made it clear, however, that he didn't think an acquittal was the right result. For example, he explained, "In this case, the prosecution chose to file murder. Granted, there's two theories that the prosecutor has in this case, but they chose to file murder. Didn't choose to file manslaughter, didn't *800choose to file justifiable homicide. Those are not issues. The issue before us is what the prosecutor chose to file, and you have to address that. You have to deal with that." Again: "We all agree people should be held responsible for what they do, but in a court situation, we're limited to what's charged. Again, it's a homicide. The prosecution has a lot of ways to charge homicide. ... The choice was made by the prosecutor here."
In the end, without an instruction on involuntary manslaughter, defense counsel was left to tell the jury this: "You know, I'd love to tell you, sure, hold Tyshaun responsible; but based on what we have here and now, this case has not been proven beyond a reasonable doubt. It's just the way it was pled."
The court's refusal to instruct the jury on the lesser-included offense of involuntary manslaughter placed defense counsel in the untenable position of arguing that his client-who had plainly killed a man-should be set free.
5.2. The evidence of malice was not overwhelming.
The People insist the court's refusal to instruct on involuntary manslaughter was harmless because "there was overwhelming evidence of malice in this case. ... [Defendant] cannot credibly claim that stomping on the victim's head and upper body 20 times did not constitute 'malice' sufficient for second degree murder."
We disagree. As discussed above, there was sufficient evidence from which a reasonable juror could conclude defendant did not intend to kill Smith. Most of Smith's injuries were nonlethal. To be sure, that defendant unwittingly chose a victim with a preexisting neck condition would usually be irrelevant, for a defendant takes his victim as he finds him and should not benefit from picking a vulnerable one. Here, however, Smith's prior neck injury speaks to defendant's subjective awareness of the consequences of his actions because it could show that defendant did not intend to beat Smith badly enough to kill him.
Nor do the People's two cited authorities-provided without any discussion or analysis-support their position.
In Moye , the court concluded any error in failing to instruct the jury sua sponte on a heat-of-passion theory of voluntary manslaughter-in addition to instructions that were given on imperfect self-defense manslaughter-was harmless under state law. ( People v. Moye (2009)
In Flood , the trial court failed to instruct the jury that to convict the defendant of evading a peace officer, the prosecution was required to prove that the defendant evaded actual peace officers. ( People v. Flood (1998)
Moreover, the Flood court noted, "the verdict demonstrate[d] that the jury resolved every contested issue in favor of the prosecution and, in particular, credited the testimony of all of the witnesses who testified regarding [the officers'] status as peace officers. On the only issue related to the 'peace officer' issue that defendant actually contested, the jury rejected defendant's contention and found that the motor vehicle in which the officers were driving was 'distinctively marked.' " ( Flood , supra , 18 Cal.4th at p. 505,
Unlike Moye , the case before us is not one in which the jury rejected other theories of guilt in favor of one requiring a more culpable mental state, indicating that if properly instructed, the jury would still have found defendant guilty of a crime greater than involuntary manslaughter. And unlike Flood , this is not a case in which the jury demonstrably decided every contested issue in favor of the prosecution and fully credited every prosecution witness. To the contrary, the jury's verdicts here-acquitting defendant of premeditated murder, acquitting defendant of felony murder, acquitting *802defendant of attempted robbery, and finding the attempted-robbery special circumstance not true-indicate it rejected the prosecution's theory of the case. Furthermore, since Angel provided the only evidence to support the attempted robbery count, the jury apparently rejected or found problematic at least some of Angel's testimony.
Nor is this a case in which the court failed to instruct on a peripheral issue, as in Moye , or a conceded element, as in Flood . Unlike the trial courts in those cases, the court here refused repeated defense requests to instruct on a lesser crime that embodied the entire defense. Here, the court refused to instruct on a lesser crime that targeted the flaws in the only element the defense contested.
*8955.3. The jury struggled with its verdict.
" 'The necessity for instructions on lesser included offenses is based in the defendant's constitutional right to have the jury determine every material issue presented by the evidence. [Citations.] ... "True, if the prosecution has not established beyond a reasonable doubt every element of the offense charged, and if no lesser offense instruction is offered, the jury must, as a theoretical matter, return a verdict of acquittal. But a defendant is entitled to a lesser offense instruction-in this context or any other-precisely because he should not be exposed to the substantial risk that the jury's practice will diverge from theory. Where one of the elements of the offense charged remains in doubt, but the defendant is plainly guilty of some offense, the jury is likely to resolve its doubts in favor of conviction." [Citation.]' [Citation.]" ( People v. Tinajero (1993)
There is evidence here that the jury struggled with just this problem. As discussed, the defense did not contest identity and conceded that defendant killed Smith. Defendant's only claim was that he lacked malice. Indeed, defense counsel acknowledged that ideally, defendant should be convicted of something, and lamented that the prosecution's charging decision placed the jury in such a difficult position. Yet without an involuntary manslaughter instruction, the jury was left to decide between first degree murder, second degree murder, and ... nothing. As we have discussed at length above, the error went to the heart of the defense case that defendant did not try to rob Smith and didn't know the beating could kill him.
The jury agreed with that theory-at least in part. Jurors acquitted defendant of premeditated murder. They acquitted him of felony murder. And they acquitted him of attempted robbery. In so doing, they rejected the prosecutor's theory of the case and at least some of Angel's testimony. (See *803People v. Mullendore (2014)
DISPOSITION
The judgment is reversed, and the matter is remanded for retrial.
WE CONCUR:
EDMON, P. J.
KALRA, J.
Because we reverse on this basis, we do not reach defendant's additional arguments.
All undesignated statutory references are to the Penal Code.
Jordan's case was subsequently transferred to juvenile court. He is not a party to this appeal.
While felony murder does not require malice, the jury in this case rejected that theory when it acquitted defendant of both first degree murder and attempted robbery and found the robbery-murder special circumstance not true. (People v. Gonzalez (2012)
Voluntary manslaughter is not at issue in this case.
An unlawful killing may also amount to involuntary manslaughter under a misdemeanor-manslaughter theory (§ 192, subd. (b) ), but that rule is not at issue here. (See, e.g., People v. Lee (1999)
Because we conclude the error here was prejudicial under state law, we do not address whether it also violated defendant's federal constitutional rights.
Judge of the Los Angeles Superior Court, assigned by the Chief Justice pursuant to article VI, section 6 of the California Constitution.