Chop shops are illegal automobile garages that buy stolen cars, disassemble them, and sell the individual parts for a profit. Chop shops often disassemble a car within hours of purchasing it from the thief who stole it—making it difficult for the police and the rightful owner to find the stolen vehicle. Chop shops are often operated in residential garages and small commercial spaces to avoid detection, but are usually part of a large criminal network or organization.

It is a crime under federal law (18 U.S.C. § 2322) to knowingly own, operate, maintain, or control a chop shop. There are significant fines and penalties under federal law for operating a chop shop—up to 15 years imprisonment for a first conviction, with the maximum fine and imprisonment doubled for any subsequent conviction.

States also have criminal laws (located in the penal or criminal code or statutes) that prohibit the operation of a chop shop. An offender may be prosecuted under state chop shop laws in addition to a federal prosecution, or instead of a federal prosecution.

In Montana, operating a chop shop is illegal under both federal and state law. Federal law, specifically 18 U.S.C. § 2322, criminalizes the knowing ownership, operation, maintenance, or control of a chop shop, with penalties including up to 15 years imprisonment for a first conviction and the possibility of doubled fines and imprisonment for subsequent convictions. Montana state law also prohibits the operation of chop shops, and individuals can be prosecuted under these state statutes. The state laws are designed to complement federal law, allowing for prosecution at the state level either in addition to or instead of federal prosecution. Penalties under state law may vary, but they typically include fines, imprisonment, or both, and are aimed at deterring the illegal disassembly and sale of stolen vehicles and their parts.