Mich. Comp. Laws § 600.2158: Crime; interest or relationship of witness, effect.

Sec. 2158.

No person shall be excluded from giving evidence on any matter, civil or criminal, by reason of crime or for any interest of such person in the matter, suit, or proceeding in question, or in the event of such matter, suit or proceeding, in which such testimony may be offered, or by reason of marital or other relationship to any party thereto; but such interest, relationship, or conviction of crime, may be shown for the purpose of drawing in question the credibility of such witness, except as is hereinafter provided.