Is there any case law where a police officer can't distinguish who was driving the car?

To be sure, and to state the obvious, "Had appellant been the driver[,] presumably there would have been no question he had possession of the car." (People v. Land, supra, 30 Cal.App.4th at p. 223, fn. 2.) Here, by contrast, the officer could not perceive who had been driving the car; defendant could have been the passenger and had no control over it. We must look to other evidence to determine if there was sufficient evidence that defendant had control of some part of the car and thus satisfied the possession element of the offense.