In Florida, you can be found guilty of DUI if you are "operating" a motor vehicle while impaired, or if you are in "actual physical control" of the vehicle. In other words, you don't have to be driving to be driving drunk. The motor doesn't even have to be running.
"Operating" versus "Actual Physical Control" may seem like a distinction without a difference, but consider this: Often, someone who has had too much to drink will call a friend or relative to pick him up. He leaves the bar, and goes to his car to wait for his ride to get there. While we have a temperate climate, there are some days when a car is over 110 degrees, and there are some evenings when it is very cool during the winter. In either case, the poor unfortunate might put the keys in the ignition and start the car, just to get the heat or the air conditioning going.
According to the Standard Florida Jury Instructions, that person may be in "actual physical control" of the motor vehicle. Only the jury can make the final decision, but the instructions say that you are in "actual physical control" if you are "on or in the vehicle and capable of operating it." In fact, the prosecution can get the case before the jury merely by showing that the keys were available to the defendant, even if the car's engine was not running.
This doesn't mean that all is lost if the police stopped you while you were waiting for your ride to arrive. As I said above, the law only tells the jury what they CAN find, and not what they MUST find.
When one of our clients is accused of being in "actual physical control" as the basis of a DUI charge, I talk to the jurors as they are being selected about how we interpret statutes. The courts presume that every word of a criminal statute is there for a reason. There are no "extra" words. There are no words which were just thrown in accidentally.
So if every word in a criminal statute has to be there for a meaning, then why did the legislature restrict DUI to people who are operating or in ACTUAL physical control of a vehicle? Why not just "physical control?" It is important for the jury to consider that the legislature wanted to restrict DUI convictions to people who were ACTUALLY physically controlling the car.
When someone gets into the car and has the keys in the ignition only for one reason--say, heat or even the radio--we think it is obvious that that person is not ACTUALLY controlling the car, but is only waiting for his ride. And that is not a crime.