Attempted manslaughter is a criminal charge brought when someone takes a direct, concrete step toward killing another person under circumstances that would qualify as manslaughter, but the victim survives. It sits between a completed manslaughter and conduct that never got off the ground, and it carries the intent requirement of an attempt alongside the reduced culpability that defines manslaughter itself. Under federal law, a conviction carries up to seven years in prison.1Office of the Law Revision Counsel. 18 USC 1113 – Attempt to Commit Murder or Manslaughter State penalties vary, but the underlying idea is consistent across jurisdictions.
An attempt, as a matter of criminal law, is an offense of incomplete conduct: someone intends a crime, moves toward committing it, and is stopped or fails before finishing.2Congressional Research Service. Attempt – An Overview of Federal Criminal Law Manslaughter is an unlawful killing that lacks the malice or premeditation of murder. Combine the two and you get a charge that targets dangerous conduct short of a completed killing but well beyond ordinary recklessness.
What Prosecutors Have to Prove
Three things generally have to be established for a conviction:
- Intent to engage in conduct that could foreseeably cause death under the circumstances. The defendant does not need to have wanted the victim dead, but must have purposefully performed the dangerous act.
- A substantial step toward completing the act. Thinking about it or planning it is not enough. The defendant has to have moved into concrete action.
- Survival of the victim. If the victim had died, the charge would be manslaughter rather than attempted manslaughter.
Most courtroom fights center on the substantial-step element. Under the Model Penal Code framework that most jurisdictions follow, the step has to be “strongly corroborative” of the defendant’s criminal purpose. Lying in wait, possessing materials specifically useful for the crime, and unlawfully entering a place where the crime was planned to occur all qualify.2Congressional Research Service. Attempt – An Overview of Federal Criminal Law Where preparation ends and a substantial step begins is a fact-specific question, and drawing that line is often the whole case.
How It Differs From Attempted Murder
The difference comes down to what was in the defendant’s mind. Attempted murder requires a specific intent to kill. The defendant must have consciously wanted the victim’s death and taken steps to bring it about. Someone who plans to shoot a specific person, pulls the trigger, and misses has committed attempted murder.
Attempted manslaughter lacks that cold purpose. It covers situations where the defendant intended to do something dangerous that could kill, but did not specifically aim to cause death. A classic example: someone discovers their spouse in an affair, grabs a heavy object in a blind rage, and strikes the other person. If the victim survives, the facts look like attempted voluntary manslaughter rather than attempted murder, because the violence was impulsive rather than calculated. The stakes in getting this distinction right are large. Attempted murder under federal law carries up to twenty years, nearly three times the ceiling for attempted manslaughter.1Office of the Law Revision Counsel. 18 USC 1113 – Attempt to Commit Murder or Manslaughter
Heat Of Passion And Imperfect Self-Defense
Two factual patterns account for most attempted voluntary manslaughter charges. Both are mitigating circumstances that pull a case down from attempted murder.
Heat Of Passion
Heat of passion applies when the defendant was provoked into such an intense emotional state that a reasonable person in the same situation might also have acted rashly. Courts look at two things: whether the provocation was objectively severe enough to unsettle a reasonable person, and whether the defendant actually lost self-control as a result. Discovering a spouse’s infidelity, being subjected to a serious physical assault, and witnessing violence against a close family member are common examples.
There is a catch. If enough time passed between the provocation and the violent act for the defendant to cool down, the heat-of-passion argument fails. Someone who is provoked, leaves, stews for two hours, then returns with a weapon has had time to reflect, and the prosecution can argue the act was deliberate enough for attempted murder instead.
Imperfect Self-Defense
Imperfect self-defense arises when the defendant genuinely believed deadly force was necessary to protect themselves or someone else, but that belief was objectively unreasonable. In jurisdictions that recognize the doctrine, it does not excuse the conduct entirely; it reduces attempted murder to attempted voluntary manslaughter. If someone honestly but unreasonably concludes they are about to be killed and responds with potentially lethal force, the charge may be reduced because the defendant was acting from a flawed read of the danger rather than from malice.
Not every state recognizes imperfect self-defense, and the details vary where it is available. The key is that the belief has to be honest but wrong. If the belief was both honest and reasonable, that is a complete defense. If it was fabricated, neither doctrine helps.
Why “Attempted Involuntary Manslaughter” Usually Does Not Exist
Involuntary manslaughter is an unintentional killing caused by recklessness or criminal negligence. Attempt, by definition, requires intent. “Attempted involuntary manslaughter” therefore asks a logically strained question: can you intentionally try to accidentally kill someone?
The near-universal answer across American jurisdictions is no. Attempt crimes require the defendant to have acted with purpose toward bringing about the criminal result. Since involuntary manslaughter’s defining feature is the absence of intent to kill or even to harm, most courts have held you cannot attempt it. Reckless endangerment can be charged separately, but the specific label “attempted involuntary manslaughter” is one most prosecutors cannot bring and most courts will not sustain. Colorado is a notable outlier: courts there have held that a defendant only needs to act with the mental state required for the completed offense and satisfy the physical requirements of an attempt, without proof that the defendant intended the prohibited result. For most of the country, though, attempted manslaughter means the voluntary variety.
Penalties
Under federal law, attempted manslaughter within the special maritime and territorial jurisdiction (which includes places like military bases, national parks, and vessels at sea) carries a maximum of seven years in prison, a fine, or both.1Office of the Law Revision Counsel. 18 USC 1113 – Attempt to Commit Murder or Manslaughter The federal sentencing guidelines route the offense through the aggravated assault guideline rather than the homicide guidelines. The base offense level starts at 14, with upward adjustments for firearm use, the seriousness of the victim’s injuries, and premeditation. Using a dangerous weapon adds up to four levels, and causing serious bodily injury adds up to seven, with combined enhancements from weapon use and injury capped at ten additional levels.3United States Sentencing Commission. Annotated 2025 Chapter 2 A-C That is a meaningfully lighter track than attempted murder, which has its own guideline with a base offense level of 27 or 33.4United States Sentencing Commission. 2A2.1 – Assault with Intent to Commit Murder; Attempted Murder
Most attempted manslaughter prosecutions happen at the state level, not the federal level. States generally treat attempted voluntary manslaughter as a felony, with prison exposure ranging from a few years to more than a decade depending on the jurisdiction and the facts. Enhancements for weapon use, victim vulnerability, or prior convictions can push actual sentences well above the base range.
Common Defenses
Beyond attacking the prosecution’s proof on each element, defendants have several available strategies.
Voluntary Abandonment
Under the Model Penal Code and the statutes of many states, a defendant can raise abandonment as an affirmative defense if they voluntarily gave up the criminal effort before completing the offense. The abandonment has to reflect a genuine change of heart. Stopping because police arrived, because the plan became harder, or because the defendant wanted to try again later does not count. The renunciation has to be complete and voluntary.
No Substantial Step
If the defendant’s conduct never crossed from mere preparation into a substantial step, there is no attempt. A defendant who thought about harming someone, or even bought supplies but never moved toward acting on them, can argue the conduct did not go far enough. This defense is fact-intensive and often hinges on exactly what the defendant did and when they stopped.
Self-Defense
Complete self-defense is a full defense to attempted manslaughter. If the defendant reasonably believed deadly force was necessary to prevent imminent death or serious injury, the use of force was justified. The gap between complete self-defense (acquittal) and imperfect self-defense (reduction from attempted murder to attempted manslaughter) matters enormously at trial, and juries often struggle with it.
How These Charges Actually Come Up
In practice, attempted manslaughter often emerges through plea negotiations rather than as the original charging decision. Prosecutors frequently file attempted murder, then offer attempted voluntary manslaughter in a plea deal. The prosecution secures a felony conviction without the risk of losing at trial on the intent-to-kill element, and the defendant takes substantially less prison time.
The charge also appears when a violent altercation leaves someone seriously injured but alive and the facts do not clearly support attempted murder. Bar fights that escalate to weapon use, road rage incidents where a driver deliberately rams another vehicle, and domestic violence situations involving serious but non-fatal injuries are common patterns. In each, the prosecution has to show the defendant intended the dangerous act, took a substantial step, and acted under circumstances that fit manslaughter rather than murder.