MI HB6432

Defines "preliminary chemical analysis" to include both preliminary chemical breath analysis and preliminary chemical oral fluids analysis (using immunochemical assay to detect controlled substances).

Amends commercial motor vehicle standards to prohibit operation with 0.015 grams or more per 100 milliliters of blood alcohol content and requires 24-hour out-of-service orders for violations or refusals.

Allows peace officers to require preliminary chemical analysis (breath or oral fluids) for drivers suspected of impairment by alcohol or controlled substances, with results admissible in criminal prosecutions and administrative hearings under specified conditions.

Requires preliminary chemical oral fluids test results to be confirmed by liquid chromatography with mass spectrometry before admission as evidence for purposes other than challenging arrest validity.

Expands controlled substance testing authority by authorizing peace officers to require preliminary chemical analysis on operators of any motor vehicle (not just commercial vehicles) suspected of driving under the influence of controlled substances.