Third Degree Murder Overview

Someone can be accused of third-degree murder if they unintentionally cause someone else's death while committing a dangerous act. This is different from first-degree and second-degree murder charges, where intent is generally required.

Only three states have third-degree murder laws: Minnesota, Florida, and Pennsylvania. Each of these three states defines third-degree murder differently, as explained in the chart below.

Third-Degree Murder in Florida, Minnesota, and Pennsylvania

*Note that states have sentencing guidelines and some have mandatory minimum sentences that affect how long someone might be imprisoned for third-degree murder. For example, Minnesota's sentencing guidelines suggest 12.5 years imprisonment for a first-offense third-degree murder. In Florida, third-degree murder carries a minimum sentence of 10 1/3 years.

What Is the Difference Between First-, Second-, and Third-Degree Murder?

Generally, states require premeditation for first-degree murder (think: the defendant developed a plan). Many states also consider causing a death while committing a felony to be first-degree murder. This is called felony murder. Other states consider felony murder to be second-degree murder.

Second-degree murder charges occur when the defendant intended to commit murder, but did not plan it in advance. Some states consider it to be second-degree murder if the defendant intended only to cause serious bodily harm but knew or should have known that death could result from the act.

Remember that not all states use the terms first-, second-, and third-degree murder in their criminal codes, and the exact definition of crimes varies by jurisdiction. As noted above, only three states have third-degree murder laws. Most states, though, have different levels of murder charges and impose lesser sentences for the lesser crime.

What Is the Difference Between Third-Degree Murder and Manslaughter?

Manslaughter charges, less serious than murder charges, arise when the defendant had no intention to kill, and didn't plan it beforehand, but their actions were reckless or negligent to the point that they could have avoided the killing by acting appropriately.

Some states break manslaughter charges into voluntary and involuntary. Others break them down into different degrees, just like with murder.

The difference between third-degree murder and manslaughter often depends on the defendant's state of mind at the time of the killing. In Minnesota, for example, someone can be convicted of manslaughter in the second degree if they knew they were unreasonably risking someone else's life and took that chance. This is different from third-degree murder, where the person must act with a depraved mind and malice (wanton disregard for human life).

First-degree manslaughter — also called heat-of-passion manslaughter, or voluntary manslaughter — occurs when someone intentionally kills another person in the heat of the moment. Generally, they must have been strongly provoked in the moment and not have had time to cool off. Unlike third-degree murder, there is intent to kill, but it is assumed a reasonable person may have lost control of their emotions when similarly provoked.

Involuntary manslaughter, on the other hand, is the least serious of the charges (though still serious) because the killing was unintentional, and possibly accidental, but caused by the defendant's reckless behavior, such as drunken driving or DUI.

Defenses Against a Third-Degree Murder Charge

Defenses to a third-degree murder charge might include:

• Innocence ("It wasn't me.")
• Insanity ("I was mentally impaired and didn't understand what I was doing.")
• Self-defense ("I was protecting myself from immediate and serious harm.")
• Defense of others ("I was protecting others from serious harm.")
• Exercise of duty ("I am a public officer who killed without unlawful intent, recklessness, or negligence.")

If you have been charged with third-degree murder, you will want to hire an experienced criminal defense lawyer to determine what defenses can be used to protect you from lifelong consequences.