Can you get charged with OWI for sleeping in your vehicle?

The short answer?  Maybe.

Michigan's drunk driving laws prohibit operating a motor vehicle or being in physical control of the vehicle while intoxicated. "Physical control" of a vehicle in other states has been interpreted broadly to include sleeping in the vehicle, so a person who is sleeping behind the wheel in Ohio might be convicted of drunk driving.  In Michigan, however, our courts have held that person must have placed the vehicle in a position of risk in order to be convicted of drunk driving.  If an intoxicated person is found to be sleeping with his or her vehicle parked in the middle of the road, it's quite likely that the person will be charged, but if a person decides to sleep it off in the bar parking lot, the person should not be charged with OWI.

In People v Keskimaki, 446 Mich. 240 (1994), the Court held that an “accident” had not occurred when a sleeping motorist had pulled off to the side of the road to sleep off the effects of alcohol: 
Consideration of these factors compels the conclusion that defendant was not involved in an accident as required under the statutory exception. We believe this result is also supportable from a policy perspective. We noted earlier that one of the purposes of the accident exception was to facilitate the safety of both the public and the drunken driver. To conclude that an accident has occurred when a drunk driver has recognized his impairment and left the road in an attempt to recover his sobriety by sleeping is to discourage the one drop of sensible conduct in a sea of irresponsible action. We do not believe the Legislature intended these consequences, and we decline to interpret "accident" in a manner both inconsistent with and subversive to our perception of the legislative intent underlying the accident exception.
Keskimaki, at 257.
In the case of People v Pomeroy (On Rehearing) and People v Fulcher (On Rehearing), 419 Mich. 441; 355 N.W.2d 98 (1984), the Michigan Supreme Court held that:
We hold that under any reasonable interpretation of the phrase "operate a vehicle", a person sleeping in a motionless car cannot be held to be presently operating a vehicle while sleeping. [Emphasis added.]
In these combined cases, the Court held that a person could not be convicted when “the defendant was arrested while asleep in his stationary car.”  The facts of the two combined cases diverge wildly. In Pomeroy, the Court described the following:
The evidence at Pomeroy's trial disclosed that two deputy sheriffs discovered him asleep and slumped over the steering wheel of a car. The car was legally parked in front of the Cornerstone Bar on Bay Street in Unionville. Pomeroy's head was resting against the horn, which was blowing. The car's standard transmission was in neutral and the motor and heater were on, but the lights were off.
. . . .
The deputies testified that Pomeroy did not actually move the car. Pomeroy testified that he had been drinking that day at the Cornerstone Bar. When he started to fall asleep, the bartender told him he could not sleep in the bar. Pomeroy  [*445]  had then asked a friend for the keys to his car so he could "go to sleep". He had turned on the car's motor and heater because it was cold. He denied any intention to actually drive the car; the friend had said he would wake Pomeroy when he came out of the bar.
While in Fulcher:
A  . . .  police officer found Fulcher's car with the rear end in a ditch and the front end on the roadway. The car's automatic transmission was in "drive" and the engine was idling. Fulcher was slumped over the wheel, but his foot was off the accelerator. The police officer had to shake Fulcher several times and shout at him before Fulcher finally woke up. Tire tracks were furrowed in the ground, following the path of the car into the ditch.
Justice Levin dissented in these combined cases, arguing that, “In Pomeroy there was not sufficient evidence that the defendant was ‘in actual physical control of a vehicle.’ In Fulcher there was sufficient evidence.”  Justice Levin’s dissent has grown to accurately represent Michigan law through case law developments and statutory changes made by the Legislature.
Eleven years later in People v Wood, 450 Mich. 399; 538 N.W.2d 351 (1995), the Michigan Supreme Court announced a new standard to be employed to determine whether a motorist was “operating” a motor vehicle.  In Wood, the driver was found unconscious and slumped over the wheel of his van, which was at the drive-through window of a restaurant. The engine was running and the gearshift was in drive, but the defendant's foot was on the brake. Wood, supra at 402. The Court held that "once a person using a motor vehicle as a motor vehicle has put the vehicle in motion, or in a position posing a significant risk of causing a collision, such a person continues to operate it until the vehicle is returned to a position posing no such risk." Id. at 404-405. The Court concluded that because the defendant had driven the van and only his foot on the brake prevented it from moving, it still posed a risk of collision and thus he was operating the vehicle. Id. at 405. 
Since Wood, prosecutors have attempted to prove an “attempt” to drive drunk.  This has been rejected.  In People v Burton, 252 Mich. App. 130; 651 N.W.2d 143 (2002), the defendant drove his truck across a parking lot. He was found asleep behind the wheel of his truck, which was still in the parking lot. The engine was running and the gearshift was either in park or neutral. Burton, supra at 132, 142. The defendant was charged and convicted of “attempted” OUIL third on the theory that he planned to drive away from the parking lot but was prevented from doing so by police intervention. Id. at 141. The Court of Appeals held that the evidence was insufficient to prove that the defendant “was intending to 'operate' his truck” because it was not in motion, it was parked, and it was not “in a position posing a significant risk of causing a collision,” given that the transmission was not in gear. Id. at 143-145.   Similarly, in People v Margaret Andres, 2006 Mich. App. LEXIS 483 (Unpublished February 23, 2006), the Court of Appeals held that the defendant was not “operating” when police discovered Defendant parked at a gas station “in the parking lot, in a white minivan that was facing a bar. Defendant smelled of intoxicants, had bloodshot eyes, spoke in a manner that was difficult to understand, failed field sobriety tests, and eventually tested for a blood alcohol level of 0.26. The van's keys were in the ignition, and the transmission was in drive, but the engine was not running, and the vehicle never moved.”  In Andres, the prosecution had sufficient evidence to establish that the motorist was so drunk that she could not figure out how to start the vehicle, but because she was physically unable to put the vehicle into a position of risk, the Court held that the charges could not stand.
The critical question in a case where the element of “operation” is at issue with a sleeping motorist frequently remains a mixed issue of law and fact as to whether the motorist had placed the vehicle “in a position of risk” while intoxicated.