(1) Except as provided in subsection (2), the presence of a dangerous drug, harmful drug, or detrimental drug in a motor vehicle, other than a public omnibus, is prima facie evidence of knowing possession thereof by each and every person in the vehicle at the time the drug was found.
(2) Subsection (1) does not apply to:
(a) Other occupants of the motor vehicle if the substance is found upon the person of one of the occupants therein;
(b) All occupants, except the driver or owner of the motor vehicle, if the substance is found in some portion of the vehicle normally accessible only to the driver or owner; or
(c) The driver of a motor vehicle who is at the time operating it for hire in the pursuit of the driver's trade, if the substance is found in a part of the vehicle used or occupied by passengers.