The crime of assault varies from state to state (and under federal law), but is generally defined as intentionally putting another person in reasonable apprehension or fear of an imminent (immediate) harmful or offensive contact. The crime of assault may be committed even if there is no physical contact, as the criminal physical contact constitutes the separate crime of battery. In many states assaulting a police officer or peace officer who is performing official duties (such as making a lawful arrest) is a more serious offense—sometimes a felony.

In New Jersey, assault is codified under N.J.S.A. 2C:12-1 and is generally categorized into simple assault and aggravated assault. Simple assault is considered a disorderly persons offense and occurs when an individual attempts to cause or purposely, knowingly, or recklessly causes bodily injury to another, or negligently causes bodily injury with a deadly weapon, or attempts by physical menace to put another in fear of imminent serious bodily injury. Aggravated assault, which is a more serious offense and can be a felony (indicted as a crime in New Jersey), involves more severe actions such as attempting to cause serious bodily injury purposely or knowingly, or causing such injury recklessly under circumstances manifesting extreme indifference to the value of human life, or assaulting a police officer or other protected public servants while they are performing their duties. The severity of the charges and penalties can increase based on factors such as the extent of injury, the use of a weapon, and the status of the victim (e.g., police officer, firefighter, teacher, etc.).