Mich. Comp. Laws § 438.151
That it shall be lawful for any person or corporation, borrowing money in this State, to make notes, bills, bonds, drafts, acceptances, mortgages, or other securities, for the payment of principal or interest, at the rates authorized by the laws of this State, payable at the place where the parties may agree, although the legal rate of interest in such place may be less than in this State; and such notes, bonds, bills, drafts, or other securities, shall not be regarded or held to be usurious, nor shall any securities taken for the same, or upon such loans be invalidated in consequence of the rate of interest of the State, kingdom or country, where the paper is made payable, being less than in this State, nor of any usury or penal law therein.
MCL 438.151