A high percentage of crime is committed when both defendants and victims are alcohol intoxicated. Forensic clinicians are regularly asked to evaluate mental states at the time of the offense for accused perpetrators and victims of alleged crime during periods of alcohol intoxication. In criminal proceedings, both defendants and victims commonly claim that alcohol intoxication absolves them of responsibility for their conduct.
“Alcohol-induced blackouts” involve a form of anterograde amnesia, where individuals continue to function socially without recording memories, due to the impact of rapidly rising blood alcohol levels on the hippocampus. The amnesia may be partial or complete. Individuals are able to engage in complex and intentional behavior without loss of consciousness and without remembering what they did. Some research indicates that memories may be reconstructed later through post-event cueing, but subjects demonstrate problems with source monitoring and may actually produce false memories.
This raises a fascinating psycholegal question: Does alcohol intoxication remove mens rea? Legally speaking, does a blackout remove intent or consent? Should a person be held responsible for their conduct during an alcohol-induced blackout?
Observers (lay persons, police officers, mental health clinicians, researchers, and alcohol counselors) cannot reliably identify level of intoxication in others. Self-report of level of intoxication is very poor as well, including estimates of BAC in self and others,though there is some evidence that drinkers can be trained to accurately detect level of intoxication.
A bibliography of literature on alcohol-induced blackout, judgment of intoxication, and associated psycholegal mental state issues is attached as a resource for working forensic clinicians.