Justice KOURLIS
delivered the Opinion of the Court.
A jury convicted the defendant, Michael Miller, of, among other things, first-degree murder (after deliberation) and first-degree felony murder, rejecting Miller’s affirmative defense of involuntary intoxication, and rejecting evidence that Miller’s voluntary intoxication had negated the requisite mental state of first-degree murder (after deliberation). Under the doctrine of merger, the felony murder conviction and the first-degree murder (after deliberation) conviction merged, giving rise to only one sentence. Upon Miller’s appeal, the court of appeals overturned the first-degree murder (after deliberation) conviction, on the basis of instructional error by the trial court. People v. Miller, No. 01CA1026, slip op. at 2, 2004 WL 916226 (Colo.App.2004) (not selected for publication). The court of appeals found plain error in the trial court’s instruction concerning the impact of the defendant’s intoxication on his culpable mental state. It held that the trial court failed to instruct the jury properly that “after deliberation” is a part of the culpable mental state of first-degree murder that can be negated by voluntary intoxication.
On remand, as requested by the People, the court of appeals permitted the People a choice between retrial of the defendant for first-degree murder or entry of a conviction on the lesser included offense of second-degree murder. The People petitioned this court for review of the court of appeals’ decision overturning the first-degree murder conviction, and in addition, requested that the felony murder conviction, rather than the conviction for second-degree murder be reinstated.1
We granted certiorari2 and now reverse. First, we resolve the conflict among our cases concerning the standard of review applicable to allegations of constitutional error in the absence of a contemporaneous objection. We hold that where the defendant fails to object at trial, the plain error standard of review applies. We thereby reserve harmless beyond a reasonable doubt review for those cases in which the defendant preserved his claim for review.
Applying a plain error standard of review in this case, we find no plain error. Plain error occurs only when, after review of the entire record, the appellate court concludes that the error undermined the fundamental fairness of the trial.
Here, in reviewing the entire record, we cannot so conclude. First, the question of voluntary intoxication was not actually contested at trial, in that the defendant did not raise it as his defense. More importantly, we find overwhelming evidence in the record to support the first-degree murder conviction. We therefore reverse the court of appeals’ [746]*746decision overturning the defendant’s first-degree murder (after deliberation) conviction.
Finally, because we overrule the court of appeals’ reversal of the first-degree murder (after deliberation) conviction, we need not reach the second issue presented. Thus, we decline to determine what the law requires when a first-degree murder conviction and felony murder conviction have merged, and the first-degree murder conviction is reversed.
We reverse and remand for reinstatement of the defendant’s first-degree murder (after deliberation) conviction.
I. FACTS
On March 8, 2000, police officers found Loyal Burner’s lacerated body in his Federal Heights, Colorado mobile home. Michael Miller, a close friend, former roommate, and employee of Burner, confessed to killing Burner and subsequently stealing several items from the victim, including his vehicle. The Adams County District Attorney charged the defendant in an information with first-degree murder (after deliberation),3 first-degree felony murder,4 aggravated robbery, three counts of first-degree aggravated motor vehicle theft, vehicular eluding, and theft. Trial was to a jury between January and February of 2001.
The defendant did not testify but, admitting responsibility for the death, he defended on grounds of self-defense to a sexual assault by the victim; involuntary intoxication caused by the victim; or alternatively, actions taken in a rage. In addition, sufficient evidence of self-induced intoxication emerged at trial, entitling him to a diminished capacity instruction, which is the subject of this petition. Evidence of Miller’s defense was introduced through his taped confession and through testimony of witnesses to whom the defendant had given varying versions of the incident. The defendant also proffered expert opinion in support of his defense of involuntary intoxication.
That evidence indicated that Miller had appeared at the victim’s home on the date of the murder after consuming a small amount of methamphetamines. The victim appeared at the door naked and carrying a gun.5 Upon entering the mobile home, Miller said the victim sexually propositioned him, including a request that Miller perform oral sex on the victim. Miller added that the victim pointed the gun at him at that moment though he understood that the act was in jest. Miller said at some point the victim had also demonstrated muffling the sound of a gun shot. The victim returned the weapon to his gun cabinet.
The victim then prepared two drinks for Miller, consisting of vodka and what appeared to be V8. Upon consuming the liquids, Miller said he felt dizzy or “delirious” and could not maintain his composure and balance. He suspected the victim had “slipped him a mickey.”6 Some time later, Miller said he located a hatchet and concealed it from the victim, anticipating that he would later have to use it to defend himself against an impending sexual assault attempt by the victim. He exited the mobile home to “catch some air” or otherwise regain his composure. He re-entered and fell asleep, or blacked out for a period of one to two hours. The defendant said he awoke in the victim’s bedroom but could not recall how he ended up there. The victim was sexually assaulting him at that moment. The victim’s gun was on the dresser, then the victim was either holding it, [747]*747or the gun was nearby the victim. Miller said he “flung” the gun away from the victim and struck him in the neck using his elbow. He then grabbed the hatchet from beneath the bed and levied several blows .to the victim’s head while the victim was “scuffling” with Miller. Miller hid behind the door and waited for the victim to bleed to death. He then used a flashlight to locate several of-the victim’s belongings, including the hatchet, several hundred dollars in cash, titles, a VCR, tools, walkie talkies, and a gun collection, all of which he placed in a box and carried to the victim’s truck. He drove away in the victim’s truck.
Autopsy results revealed that the victim was struck four times in the same location of his head and that he .died in the early morning hours of March 5, 2000. The forensic pathologist testified that the location of the victim’s wounds was consistent with his being in a stationary position when struck and therefore not “scuffling.”7 Also, although the defendant told police that the victim had made him perform oral sex on the victim while he, Miller, was unconscious, DNA tests did not discover the defendant’s saliva DNA on the victim. Lastly, although Miller claimed to have struck the victim in the neck with his elbow while they were scuffling, autopsy results revealed no signs of trauma to the victim’s neck.
Federal Heights police first contacted Miller on March 10, two days after discovering Burner’s body. Miller informed them that he had last seen the victim in the early evening of March 4, stating the victim had dropped him off after they had gone four-wheeling. Miller offered that he was with a friend, Nathasha Zimmerman, near the time of the murder. Zimmerman testified that, shortly after he spoke with police, Miller contacted her to serve as false alibi for him and asked her to dispose of certain items he took from the victim’s home. Furthermore, several witnesses revealed different versions of the circumstances surrounding the murder as disclosed by Miller. Those versions did not include sexual assault, or suspicions of a “mickey” in his drink,- or drunkenness. Lastly, the jury also heard testimony from Miller’s girlfriend indicating that he “waited for the right moment” to strike the victim with the hatchet.
At the close of trial, the court gave the jury several instructions relating to the culpable mental state of first-degree murder (after deliberation). The court instructed the jury on the defendant’s affirmative defense of involuntary intoxication, and that instruction is not at issue here. Concerning the impact of voluntary intoxication on the culpable mental state, the court, directed the jury to consider “evidence of self-induced intoxication in determining” whether it “negates the existence of the culpable mental state of specific intent.” The court also informed the jury that they must find the defendant not guilty if they found that he “was intoxicated to such a degree that he did not form the specific intent, which is a required element of Murder in the First-degree After Deliberation.” In separate instructions, the court informed the jury that “after deliberation” is an element of first-degree murder and that the defendant raised an affirmative defense (of involuntary intoxication). The court also gave the jury a definition of “after deliberation” and informed the jury that “after deliberation” and “intent” form part of the culpable mental state of first-degree murder. The court did not give the jury a definition of “specific intent” and did not instruct the jury that it could consider evidence of self-induced intoxication for purposes of negating the after deliberation element of first-degree murder. Miller did not object to the instructions or tender alternative instructions.
The jury returned guilty verdicts on all counts. Miller appealed, contending, in part, that the jury instructions impermissibly lowered the People’s burden of proving beyond a reasonable doubt that he premeditated the murder.
The court of appeals reversed Miller’s first-degree murder conviction, finding re[748]*748versible error in the trial court’s failure to instruct the jury specifically that it could consider evidence of intoxication as negating the “after deliberation” element of first-degree murder. Miller, No. 01CA1026, slip op. at 2. The court found the instruction inconsistent with our decision in People v. Harlan, 8 P.3d 448 (Colo.2000). Id. at 4. The court was persuaded that, faced with evidence that Miller was intoxicated at the time of the murder, the jury might have found him guilty even after surmising that he did not commit the murder after the requisite deliberation. Id. at 5. It therefore concluded that the trial court committed plain error. Id.
The People petitioned from that decision and we granted the petition.
II. CONSTITUTIONAL ERROR REVIEW
Before addressing the merits of the People’s case, we first consider the conflict among our cases concerning the appropriate standard of review for unobjected-to constitutional errors. As noted, the defendant did not object to the diminished capacity instruction the trial court gave the jury. Nonetheless, he posits that the challenged instruction is an error of constitutional dimension which requires reversal unless proved harmless beyond a reasonable doubt, even if not preserved at trial.
Our cases are contradictory on the question of whether a contemporaneous objection is required for the application of a constitutional harmless error standard of review. See Auman v. People, 109 P.3d 647 (Colo.2005) (noting conflicts). We have, at times, refused to apply that standard in the absence of an objection, holding instead that plain error controls our review of unpreserved constitutional claims. See People v. Garcia, 28 P.3d 340, 344 (Colo.2001); People v. Griego, 19 P.3d 1, 8 (Colo.2001); People v. Dunlap, 975 P.2d 723, 737 (Colo.1999); Walker v. People, 932 P.2d 303, 311 (Colo.1997); People v. Rubanowitz, 688 P.2d 231, 239 (Colo.1984). On other, occasions, we have resolved that where the challenged matter is of constitutional dimension, the error must be proved harmless beyond a reasonable doubt even if no objection was proffered. See People v. Harlan, 8 P.3d 448, 490 (Colo.2000); People v. Davis, 794 P.2d 159, 189 (Colo.1990); People v. Rodgers, 756 P.2d 980, 984 (Colo.1988); People v. Graham, 705 P.2d 505, 509 (Colo.1985).
This latter proposition is inconsistent with the current direction from the United States Supreme Court. Originally, our eases applying constitutional harmless error analysis to unobjected-to constitutional errors found root in the Supreme Court’s statement in Chapman v. California, 386 U.S. 18, 87 S.Ct. 824, 17 L.Ed.2d 705 (1967). See Rodgers, 756 P.2d at 984; Graham, 705 P.2d at 509; see also Davis, 794 P.2d at 189 (relying on Rodgers); Harlan, 8 P.3d at 490 (relying on Rodgers, Graham, and Davis). In Chapman, the Court affirmatively rejected an automatic or per se reversal rule for all constitutional errors, concluding that some constitutional errors are subject to harmless error analysis. 386 U.S. at 19, 87 S.Ct. 824; see also Rose v. Clark, 478 U.S. 570, 578, 106 S.Ct. 3101, 92 L.Ed.2d 460 (1986); United States v. Hasting, 461 U.S. 499, 103 S.Ct. 1974, 76 L.Ed.2d 96 (1983). The Court then fashioned the applicable harmless error standard for review of constitutional errors — that the error must be found harmless beyond a reasonable doubt. Id. at 22, 87 S.Ct. 824. The Court, however, did not address whether constitutional errors are also subject to plain error analysis. Rather, the court was presented with the narrow issue, “Where there is a violation of the rule of Griffin v. California, 380 U.S. 609, 85 S.Ct. 1229, 14 L.Ed.2d 106, can the error be held harmless.”8 Id. at 18, 87 S.Ct. 824.
The Court’s more recent decisions have, however, made clear that even constitutional errors are subject to a plain error standard of review. In United States v. Olano, 507 U.S. 725, 731, 113 S.Ct. 1770, 123 L.Ed.2d 508 (1993), the Supreme Court held that unpreserved constitutional claims are subject to plain error analysis. In so doing, the [749]*749Court reaffirmed the fundamental precept governing relinquishment of unpreserved claims: “ ‘No procedural principle is more familiar to this Court than that a constitutional right,’ or a right of any other sort, ‘may be forfeited in criminal as well as civil eases by the failure to make timely assertion of the right before a tribunal having jurisdiction to determine it.’ ” Id. Shortly thereafter, the Court reaffirmed Olano in Johnson v. United States, applying plain error to the trial court’s erroneous failure to submit an element of the crime to the jury, when the defendant failed to object contemporaneously to the instruction. 520 U.S. 461, 463, 117 S.Ct. 1544, 137 L.Ed.2d 718 (1997).
Three years later in Neder v. United States, 527 U.S. 1, 119 S.Ct. 1827, 144 L.Ed.2d 35 (1999), the Supreme Court appeared to lay to rest any doubt about whether constitutional harmless error analysis applies to all errors of constitutional magnitude. There, faced with an issue similar to that addressed in Chapman, the Court distinguished between errors that “defy analysis by harmless error standards,” and therefore mandate automatic reversal, and those that, upon objection by the defendant, are subject to harmless beyond a reasonable doubt analysis. Id. at 7, 119 S.Ct. 1827. The Court identified structural errors, “defects affecting the framework within which the trial proceeds,” as those demanding automatic reversal. Id. at 8, 119 S.Ct. 1827. In contrast, “trial errors,” that is, “errors in the trial process itself,” may be subject to either harmless error or plain error analysis. Id. at 8-9,119 S.Ct. 1827.9
The Court did not disapprove of its prior holdings in which it had applied plain error analysis to constitutional errors. To the contrary, it found those decisions “instructive.” Id. at 8, 119 S.Ct. 1827. Addressing Johnson, the Court classified elemental omissions and mis-deseriptions as trial errors, pointing out that it had applied plain error where the defendant failed to object to the trial court’s omission of an element in the jury instruction. See Id. The interplay between Neder and Johnson illustrates the Court’s preferred treatment of trial errors in which the defendant fails to object. The Court addressed almost identical issues in both cases, namely, the standard of review where the trial court failed to submit the element of materiality to the jury.10 In Neder, 527 U.S. at 5, 119 S.Ct. 1827, the defendant objected, while in Johnson, the defendant did not object, 520 U.S. at 463, 117 S.Ct. 1544. In Neder, 521 U.S. at 8, 119 S.Ct. 1827, finding the instructional error to be one of constitutional magnitude not mandating automatic reversal, the Court applied constitutional harmless error analysis; but the court subjected the unobjected-to claim in Johnson, 520 U.S. at 463, 117 S.Ct. 1544, to plain error analysis.
We adopted Neder ⅛ holding in Grie-go, declaring that “trial errors of constitutional magnitude are compatible with both harmless error and plain error analysis.” 19 P.3d at 8. We made clear that if the defendant lodges no objection to the evidence or procedure, then we consider the error only under the plain error standard. Id. We emphasized, as the Supreme Court did in Ned-er, that this rule applies to both instructional omission and mis-descriptions of an element of an offense. Id. Accordingly, we “expressly disapproved] of our contrary precedent on this issue.” Id. Today, we clarify that constitutional harmless error analysis is reserved for those cases in which the defendant preserved his claim for review by raising a contemporaneous objection. To the extent that some of our prior holdings state otherwise, we overrule those contrary statements.
[750]*750Plain error addresses error that is both “obvious and substantial.” See People v. Stewart, 55 P.3d 107, 119 (Colo.2002); see also Olano, 507 U.S. at 733, 113 S.Ct. 1770 (stating “‘plain’ is synonymous with ‘clear’ or, equivalently, ‘obvious’ ”). We have recognized as plain error those errors that “so undermined the fundamental fairness of the trial itself so as to cast serious doubt on the reliability of the judgment of conviction.” People v. Sepulveda, 65 P.3d 1002, 1006 (Colo.2003); Garcia, 28 P.3d at 344; Bogdanov v. People, 941 P.2d 247, 255 (Colo.1997), disapproved on other grounds by Griego, 19 P.3d at 1.
As applied to jury instructions, the defendant must “demonstrate not only that the instruction affected a substantial right, but also that the record reveals a reasonable possibility that the error contributed to his conviction.” Garcia, 28 P.3d at 344. Specifically, the court’s failure to instruct the jury properly does not constitute plain error if the relevant instruction, read in conjunction with other instructions, adequately informs the jury of the law. See Harlan, 8 P.3d at 472 (holding error not reversible where jury instructions as a whole kept prosecution to its proper burden of proof concerning the elements of first-degree murder); Garcia, 28 P.3d at 345 n. 3; People v. Manier, 184 Colo. 44, 53, 518 P.2d 811, 816 (1974). Moreover, an erroneous jury instruction does not normally constitute plain error where the issue is not contested at trial or where the record contains overwhelming evidence of the defendant’s guilt. Bogdanov, 941 P.2d at 255; Espinoza v. People, 712 P.2d 476, 478 (Colo.1985).
III. ANALYSIS
A. Voluntary and Involuntary Intoxication
In this case, Miller defended on grounds of self-defense and involuntary intoxication— that he was “slipped a mickey.” There is no dispute concerning the instructions addressing the involuntary intoxication. The evidence i-aised the question of voluntary intoxication, and the instructions on that issue are the subject of this opinion.
For clarification, we begin our analysis by discussing the differences between the two defenses. In Colorado, involuntary intoxication is an affirmative defense to a criminal charge. A defense of involuntary intoxication presumes that “[a] person is not criminally responsible for his conduct if,” because of involuntary intoxication, “he lacks capacity to conform his conduct to the requirements of the law.” § 18-1-804(3). Affirmative defenses admit the doing of the act charged but seek to justify, excuse, or mitigate it. Huckleberry v. People, 768 P.2d 1235, 1238 (Colo.1989). Affirmative defenses, including involuntary intoxication, do not simply challenge the existence of an element of the offense, but seek to justify or mitigate the entire crime, and are therefore complete defenses. See Turner v. People, 680 P.2d 1290, 1292 (Colo.App.1983).
To the contrary, voluntary or self-induced intoxication is not an affirmative defense, see Harlan, 8 P.3d at 470, but evidence of intoxication may “negative the existence of a specific intent if such intent is an element of the crime charged.” § 18-1-803(1). First-degree murder (after deliberation) is a specific intent crime. A person commits the crime of murder in the first-degree if, “after deliberation and with the intent to cause the death of a person”, he causes the death of that person. § 18-3-102(1).
Accordingly, evidence of voluntary intoxication is admissible to counter the specific intent element of first-degree murder. “After deliberation” and “intent” are two distinct elements, which together constitute the specific intent mental state of first-degree murder. See Id.; § 18—3—102(1)(a), C.R.S. (2004). The statute defines the term “after deliberation” to mean “not only intentionally but also that the decision to commit the act has been made after the exercise of reflection and judgment concerning the act.” § 18-3-101(3). Because the statute indicates that the mental state of “after deliberation” includes intent, the mental state for first-degree murder is distinguished by the requirement of “reflection and judgment.” See Harlan, 8 P.3d at 474. Voluntary intoxication, therefore, bears upon both “after deliberation” and “intent”. Id.
[751]*751B. The Instructional Error
In Instruction 11, the trial court provided general definitions of “after deliberation” and “intent.” In Instruction 12, the court set forth the elements of first-degree murder, as including both intent and after deliberation. In Instruction 31, the court charged the jury that:
You may consider evidence of self-induced intoxication in determining whether or not [s]elf-induced intoxication negates the existence of the culpable mental state of specific intent.
The prosecution has the burden of proving all the elements of the crimes charged. If you find the defendant was intoxicated to such a degree that he did not form the specific intent which is a required element of Murder in the First-degree After Deliberation and Theft you should find the defendant not guilty of those charges.
The court did not instruct that “specific intent” includes both “intent” and “after deliberation.” The court should have framed the instruction to clarify that if the jury found the defendant was intoxicated to such a degree that he did not form the intent or that he did not deliberate, both of which are required elements of Murder in the First-degree After Deliberation, the jury should find the defendant not guilty of that charge.
That is the fundamental thrust of our holding on this point in Harlan. In Harlan, we found the error not to be reversible because, when looking at the instructions as a whole, the court did direct the jury to consider evidence of voluntary intoxication as it related both to intent and to deliberation.11
In sum, when a voluntary intoxication instruction is warranted, the trial court should affirmatively instruct the jury that “after deliberation” is part of the culpable mental state required by first-degree murder and may be negated by evidence of voluntary intoxication.
IV. APPLICATION OF PLAIN ERROR STANDARD
When there is no objection to that instructional omission, the court will review the error under a plain error standard of review. Failure to instruct the jury properly does not constitute plain error where the subject of the error is not contested at trial, or where evidence of guilt is overwhelming. Bogdanov, 941 P.2d at 255. Such analysis demands that the court review the record in its entirety.
Here, first, we note that the question of defendant’s voluntary intoxication as it bore upon his intent and upon deliberation was not actually contested at trial. The defendant did not argue at trial that his voluntary intoxication should negate the specific intent required for first-degree murder. Rather, he argued that he was involuntarily intoxicated by the victim, who sexually assaulted and provoked him.
Moreover, the record here presents overwhelming evidence of the defendant’s guilt. The jury had before it evidence that, despite the defendant’s claim of involuntary intoxication, he had sufficient presence of mind to conceal the murder weapon, a sixteen inch hatchet, from the victim; and that he had the ability to later locate the weapon after “waiting for the right moment” to use it. The evidence at trial indicated that the defendant had an opportunity to leave the victim’s home, having exited the mobile home at one point, and he nonetheless returned. The jury also heard varying versions of the defendant’s story from several witnesses who testified that the defendant did not claim that he was intoxicated or drugged during the murder.
Miller even proffered expert testimony to support his defense of involuntary intoxication, to wit: his symptoms on the night of the murder, including dizziness and inability to maintain his balance supported the conclusion that the victim had drugged him. However, the defense expert conceded on cross-examination that the evidence was more con[752]*752sistent with drunkenness due to the consumption of alcohol and methamphetamines. The evidence supporting that conclusion was identified as: the fact that the defendant “blacked out” rather than “passed out”; the fact that he blacked out for only one hour rather than eight or twelve hours as is customary with Rohypnol; the fact that the defendant had a vivid memory of the morning of the murder; and the fact of the defendant’s calculating behavior immediately following the murder. Even the conclusion that the defendant experienced symptoms of drunkenness upon consuming two alcoholic beverages was undermined by evidence that drinking alcohol after consuming a small amount of methamphetamine has the effect of canceling out the alcohol: that is, methamphetamine consumption causes a high, while alcohol causes a low.
Furthermore, the defendant’s claims of self-defense were contradicted by forensic evidence. Miller defended on grounds of self-defense, claiming that the victim sexually assaulted him and that the victim had been “scuffling” with him at the time of the murder. Forensic evidence demonstrated, however, that the victim was most likely in a stationery position when struck by the defendant, and therefore, could not have been “scuffling” with him. Also, the defendant’s claims of forced oral sex were negated by DNA tests, in that there was no evidence of the defendant’s DNA saliva on the victim.
In addition, the defendant’s behavior immediately following the murder was more demonstrative of calculation and design than of “delirious,” “unconscious” action. After committing the murder, the defendant waited for the victim to take his last breath. Then, to evade detection, he used a flashlight to locate several of the victim’s belongings, including the victim’s vehicle and a significant amount of cash, with which he absconded.
We conclude therefore that the instructional error did not rise to the level of plain error.
Y. CONCLUSION
We hold that constitutional harmless error review applies only if the defendant preserves his claim for review by tendering a contemporaneous objection. Where, as in this case, the defendant fails to object at trial, plain error applies. Applying plain error to this case, we hold that the trial court’s failure to instruct the jury properly that “after deliberation” is an element of first-degree murder that is negated by voluntary intoxication did not constitute plain error. We reverse and remand for proceedings consistent with this opinion.
Justice BENDER specially concurs, and Justice MARTINEZ joins in the special concurrence.