The defense of "unconsciousness" is theoretically available to defendants in DUI cases, but only in very specific and isolated circumstances. The Prosecution in a DUI case does not have to prove that a defendant intended to drive while impaired. The elements of the offense require that there be proof of driving and at the time of driving, the defendant was legally impaired or over the legal limit of .08% breath or blood alcohol level.
However, if a person is legally "unconscious" at the time of the offense, he or she is not legally responsible. The defense is only available in circumstances where the intoxication leading to the state of unconsciousness was involuntary. If a person voluntarily gets drunk, and drives while unconscious, the defense is not available.
The question that presents itself is; How can a person drive while unconscious? CALCRIM Jury Instruction 3425 indicates that a person may be legally unconscious if he or she is "not conscious of his actions. Someone may be unconscious even though able to move. Unconsciousness may be caused by a blackout, or an epileptic seizure or involuntary intoxication or sleepwalking."
The defense may cover the situation where a defendant is drugged by another without them knowing it, although it may be difficult to prove the facts to a jury. I once had a case where a truck driver had finished work for the day and took some ambien to help him sleep in his truck. The next thing he knew, he was waking up having driven his truck into a wall.
He was unconscious at the time and had effectively "sleep driven". He was charged with DUI based on the drug ambien. In these circumstances, the defense of unconsciousness would have been viable, although the prosecution would have attempted to argue that the impairment was voluntary. I did not have an opportunity to argue the case in jury trial as the district attorneys office rejected the filing.
If you have been arrested for a DUI in Los Angeles, please call drunk driving defense lawyers Gold & Witham for a free case evaluation.