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MADISON - This morning, the Wisconsin Court of Appeals held that juries may properly rely on circumstantial evidence to prove that a defendant "operated" a vehicle while under the influence of alcohol or other drugs.


A Waukesha County jury convicted Michael G. Mertes of operating after revocation (first offense) and operating a motor vehicle with a detectable amount of a restricted controlled substance in his blood (fifth and subsequent offense). Mertes appealed his convictions on the ground that the trial evidence was insufficient to prove that he operated the motor vehicle in which he was found asleep in the driver's seat at a New Berlin gas station. He stipulated with the State at his trial that a blood sample taken from him within two hours of his arrest tested positive for cocaine and a cocaine metabolite. His sole objection to his convictions was that the trial evidence did not establish that he had operated the vehicle.


The court of appeals expressly adopted the State's analysis in upholding Mertes's convictions:


Circumstantial evidence is evidence from which a jury may logically find other facts according to common knowledge and experience . . . . Here, the State's case was built on circumstantial evidence-or, as the State characterizes it, "the entirely reasonable inference that Mertes had operated the car before the police ever arrived on the scene by driving it into the gas station." The circumstantial evidence underlying the State's theory included: (1) Mertes sitting behind the wheel of a vehicle parked at a gas pump with the keys in the ignition in the auxiliary position, (2) his statement that he had been there for approximately ten minutes, (3) his statement that he had come from Milwaukee and was headed back to Milwaukee, and (4) the lack of any evidence to suggest that the passenger (or any other specifically identified individual) had operated the vehicle-indeed [Officer] Rocklewitz testified that the passenger in the vehicle was incoherent and unable to remain awake. As the State aptly points out, "Vehicles do not simply materialize next to gas pumps at filling stations. They are driven to such locations."


The decision drew quick praise from Wisconsin Attorney General J.B. Van Hollen, whose office handled the appeal for the State. "Drunk and impaired drivers put all of us at risk," said Van Hollen. "By affirming this conviction, the court of appeals upheld the jury's ability to draw reasonable conclusions from the evidence and validated an important jury verdict. This prosecution and this decision will be an asset in law enforcement's fight against impaired driving."


Michael G. Mertes is currently incarcerated at the Kettle Moraine Correctional Institution in Plymouth, Wisconsin.


Today's decision of the Wisconsin Court of Appeals in State of Wisconsin v. Michael G. Mertes appears on the court's website:


The Waukesha County District Attorney's Office prosecuted the case in the circuit court. Assistant Attorney General William L. Gansner represented the State of Wisconsin in the court of appeals.