Murder is divided into three categories in the US legal system: first-degree murder, second-degree murder, and third-degree murder. The classification of the murder depends on the circumstances in which the murder was committed, including the reasons for the murder, the weapon used, and whether the crime was premeditated and performed with intent. Here are the key differences between the three degrees of murder:

1. First-degree murder: This is the most severe form of murder and requires an intentional murder that is willful, premeditated, and committed with malice aforethought. The element of premeditation means that the defendant must have planned the murder beforehand, but it does not require that the defendant have an extensive plan. First-degree murder is always punished with the most severe penalty of any crime, which is death or life imprisonment without parole.

2. Second-degree murder: This type of murder cannot be premeditated, but it requires that the defendant acted with intent and understanding of their actions. Second-degree murder usually occurs in the course of committing a felony crime such as robbery or burglary. Conviction on second-degree murder charges leads to life imprisonment without parole.

3. Third-degree murder: This is the lowest level of criminal homicide and includes all other homicides that do not fall under first-degree or second-degree murder. Third-degree murder is characterized by recklessness or inattention. A crime of passion, in which...