Michigan Compiled Laws, Chapter 324. Natural Resources and Environmental Protection § 324.80183

Sec. 80183. (1) The provisions of sections 80181 and 80182  1 relating to chemical testing do not limit the introduction of any other competent evidence bearing upon the question of whether or not a person was impaired by, or under the influence of, alcoholic liquor or a controlled substance, or both, or whether the person had a blood alcohol content of 0.08 grams or more per 100 milliliters of blood, per 210 liters of breath, or per 67 milliliters of urine, or whether the person had any amount of a controlled substance listed in schedule 1 under section 7212 of the public health code, 1978 PA 368, MCL 333.7212, or a rule promulgated under that section, or of a controlled substance described in section 7214(a)(iv) of the public health code, 1978 PA 368, MCL 333.7214, in his or her body.

(2) If a chemical test described in sections 80181 and 80182 is administered, the results of the test shall be made available to the person charged or the person's attorney upon written request to the prosecution, with a copy of the request filed with the court. The prosecution shall furnish the results at least 2 days before the day of the trial. The results of the test shall be offered as evidence by the prosecution in that trial. Failure to fully comply with the request bars the admission of the results into evidence by the prosecution.