Mich. Comp. Laws § 124.460
The organization, existence, membership, and all acts taken before the effective date of this act by an authority incorporated or purporting to be incorporated under Act No. 55 of the Public Acts of 1963, being sections 124.351 to 124.359 of the Michigan Compiled Laws; an authority having a population of less than 1,000,000 incorporated or purporting to be incorporated under the metropolitan transportation authorities act of 1967, Act No. 204 of the Public Acts of 1967, being sections 124.401 to 124.425 of the Michigan Compiled Laws; or an authority created or purported to be created under an interlocal agreement pursuant to Act No. 7 of the Public Acts of 1967, being sections 124.501 to 124.512 of the Michigan Compiled Laws, are hereby validated and ratified.
MCL 124.460