It is a criminal offense to use or operate a motor vehicle, boat, airplane, motorcycle, or other motor-propelled vehicle without the consent of the owner or other person authorized to give consent. This crime is generally known as (1) unauthorized use of a motor vehicle, (2) unauthorized use of a vehicle, or (3) joyriding.

The difference between this crime and the crime of theft is that the state does not have to prove a person charged with unauthorized use of a motor vehicle intended to keep the vehicle or permanently deprive the owner of the vehicle.

Laws regarding the unauthorized use of a motor vehicle vary from state to state and are generally found in a state’s statutes—often in the penal or criminal code or the vehicle code.

In Idaho, the unauthorized use of a motor vehicle, often referred to as 'joyriding,' is a criminal offense under Idaho Code § 49-228. This statute makes it illegal for any person to use or operate a motor vehicle without the consent of the owner or the owner's authorized agent. Unlike theft, the prosecution does not need to prove that the individual intended to permanently deprive the owner of the vehicle; it is sufficient to show that the vehicle was used without permission. The crime is typically considered a misdemeanor, but it can be elevated to a felony under certain circumstances, such as when the unauthorized use involves aggravating factors or if the individual has prior convictions for similar offenses. Penalties for unauthorized use of a motor vehicle in Idaho can include fines, imprisonment, or both, depending on the severity of the offense and the offender's criminal history.