The first issue is whether the person actually "drove a motor vehicle" in violation of one of the Vehicle Code Sections. Thus, two relevant issues arise from this issue and then there are applicable sub-issues:
1. Did the Licensee “Drive”? and
2. Was the Licensee Driving a “Motor Vehicle”?
Did the Officer Actually Observe the Licensee “Driving”?
This issue requires that the DMV prove that the person actually "drove" a motor vehicle. The act of “driving”, at least for purposes of the California drunk driving law statutes in California, requires a showing of “volitional movement”. Therefore, the licensee must have actually "driven" a motor vehicle pursuant to Mercer v. Department of Motor Vehicles (1991).
Under Mercer, even the “slightest movement of the vehicle” constitutes “volitional movement” for purposes of California’s Drunk Driving statutes.
How is Driving Determined If I Were in a Traffic Collision?
Proving the element of "driving", in cases involving a traffic collision can be proven by circumstantial evidence pursuant to Vehicle Code Section 40300.5. The same is true for cases involving vehicles parked along a highway or roadway when there is enough information to demonstrate recency of driving.
Note that cases distinguish between driving with the intent to drive rather than driving to safely exit a roadway for purposes of necessity, such as the following two cases that left open these exceptions:
Hensley v. Department of Motor Vehicles (1985) and People v Kelley (1937).