In my opinion, the no driving defense is the best defense because it is the defense most jurors will often rely upon to acquit.
Most of the time, the arresting officer sees the motorist driving before the stop, so the “no-driving” defense will not fly. Sometimes, the arresting officer has not actually seen the suspected driver drive the car because the car was crashed into a pole or in a ditch. Sometimes, the officer has found the suspected driver sleep in the front seat of a vehicle legally parked, with the transmission in neutral, the headlights and wipers on, and the engine running. In some scenarios, the no driving defense can be used to raise a reasonable doubt that the driver was DUI and can lead to an acquittal
The bottom line is that the prosecution always has the burden of proof beyond a reasonable doubt that, a) the driver caused volitional movement of the vehicle, and b), that the blood/breath /urine /urine test was taken within three hours of the alleged time of driving, before they can convict a driver of DUI.
Even if you are drunk as a skunk, if no one saw you driving, then the prosecution may not be able to prove its case. Why? In cases where no one saw the driving, the prosecution cannot prove a critical element of Vehicle Code section 23152(a) or (b), the fact of driving. Also, if there is no proof of the actual time when the accident occurred, the prosecution cannot prove that the alcohol test was obtained within three hours of the time of driving as required under California Vehicle Code section 23152(b). If the prosecution cannot prove that the test was taken within three hours of the time of driving they cannot prove beyond a reasonable doubt that the driver was drunk at the time of the accident.
Therefore, you should always get an attorney if there was an accident or if the arresting officer did not see the driving.