Not a lawyer either, and haven't really looked for the definition of "drive a motor vehicle or while driving."
This may help though (not necessarily specific to the situation, but might help form an argument):
Vehicle code Definitions
463. "Park or parking" shall mean the standing of a vehicle,
whether occupied or not, otherwise than temporarily for the purpose
of and while actually engaged in loading or unloading merchandise or
530. A "roadway" is that portion of a highway improved, designed,
or ordinarily used for vehicular travel.
587. "Stop or stopping" when prohibited shall mean any cessation of
movement of a vehicle, whether occupied or not, except when
necessary to avoid conflict with other traffic or in compliance with
the direction of a police officer or official traffic control device
590. "Street" is a way or place of whatever nature, publicly
maintained and open to the use of the public for purposes of
vehicular travel. Street includes highway.
Here's a portion of VEHICLE CODE
22500. No person shall stop, park, or leave standing any vehicle
whether attended or unattended, except when necessary to avoid
conflict with other traffic or in compliance with the directions of a
peace officer or official traffic control device....
You never know, just the simple act of contesting a ticket with an argument that makes some semblance of logical sense can be enough to have a ticket dismissed.