Mich. Comp. Laws § 712A.18g

Sec. 18g. (1) In addition to any other disposition under this act, a juvenile other than a juvenile sentenced in the same manner as an adult under section 18(1)(p) of this chapter shall be committed under section 18(1)(e) of this chapter to a detention facility for a specified period of time if all of the following circumstances exist: (a) The juvenile is under the jurisdiction of the juvenile division of the probate court under section 2(a)(1) of this chapter. (b) The juvenile is adjudicated as or convicted of violating a criminal municipal ordinance or law of this state or the United States. (c) The juvenile is found to have used a firearm during the criminal violation. (2) The period of time specified under subsection (1) must not exceed the length of the sentence that could have been imposed if the juvenile had been sentenced as an adult. (3) As used in this section, "firearm" means that term as defined in section 3t of 1846 RS 1, MCL 8.3t.