Unconsciousness as a Defense to Criminal Charges

Unconsciousness—or automatism—can be a defense.

By Micah Schwartzbach, Attorney

Almost all crimes require both mens rea (“guilty mind”) and actus reus (“guilty act”). Without either, there’s typically no offense. That’s why many courts recognize unconsciousness as a defense to criminal charges.  

Some courts have found that unconsciousness (sometimes called automatism) prevents a defendant from acting with a guilty mind. Others have determined that it means a defendant couldn’t have committed a guilty act—because there’s been no voluntary movement of the body.

Unconscious States

Courts have recognized that unconsciousness can by triggered by, among other causes:

• blackout
• epileptic seizure
• head injury
• involuntary intoxication, or
• somnambulism (sleepwalking).

In some states, the defendant need only present evidence of unconsciousness; after presenting that evidence, it becomes the prosecution’s burden to prove consciousness beyond a reasonable doubt. In other states, though, unconsciousness is an affirmative defense that the defendant must prove.

Importantly, courts have held that a defendant’s knowledge that he or she is susceptible to unconsciousness can sometimes negate the defense. Take, for example, a driver who gets behind the wheel knowing that he often falls victim to blackouts. (SeeFulcher v. State, 633 P.2d 142 (Wyo. 1981).)

Judges have also tended to hold that unconsciousness brought about by the choice to drink or do drugs is no defense to general intent crimes.

The Defense in Action

Suppose one car collides with another in a fender bender. The drivers, Oliver and Malcolm, get out of their vehicles and approach one another. Oliver insists that Malcolm caused the accident by braking suddenly. Malcolm angrily denies the accusation, countering that Oliver must have been eyeing his smartphone rather than the road. As Oliver begins to turn to gather his insurance information from his car, Malcolm’s clenched fist hits him squarely in the left temple. A dazed Oliver swings back at Malcolm, knocking his adversary to the ground. As horrified pedestrians and motorists look on, Oliver jumps on his supine attacker. He punches Malcolm, who is unresponsive, in the face several times.

Prosecutors charge Oliver with assault likely to cause great bodily injury. At trial, they argue that, even if he initially defended himself, Oliver committed the crime by pounding the defenseless Malcolm. They contend that Oliver used more force than was reasonably necessary to defend himself.

Oliver’s defense team counters that their client wasn’t “there” when tuning up the alleged victim. His lawyers argue that the head injury caused by Malcolm’s punch rendered him unconscious. The defense presents a medical expert who testifies that Malcolm’s blow could very well have led to unconsciousness even though Oliver remained capable of physical movement.

At the end of the case, the judge gives the following jury instruction:

The defendant is not guilty of assault if he acted while unconscious. Someone is unconscious when he or she is not conscious of his or her actions.

Unconsciousness can exist where a subject physically acts in fact, but is not, at the time, conscious of acting.

Unconsciousness may be caused by a head injury.

The prosecution must prove beyond a reasonable doubt that the defendant was conscious when he acted. If there is proof beyond a reasonable doubt that the defendant acted as if he were conscious, you should conclude that he was conscious, unless based upon all the evidence, you have a reasonable doubt that he was conscious, in which case you must find him not guilty.

(See Judicial Council of California Criminal Jury Instruction 3425.)

The jurors, armed with this instruction and medical testimony from the defense, are left to decide whether Oliver could have been unconscious. If they have a reasonable doubt, they must acquit.