Intoxication due to a defendant’s voluntary consumption of drugs or alcohol isn’t usually a defense to criminal charges—but if the intoxication was involuntary, it may be a defense on the basis that the defendant did not understand what he was doing or that what he was doing was wrong. And some states allow a defendant to assert a defense that his voluntary intoxication prevented him from forming the specific intent to commit the crime (attempted murder, for example). But this is a question of fact that the jury will usually determine.

The availability and definition of any defense to criminal charges based on the defendant’s voluntary or involuntary intoxication is usually located in a state’s statutes—often in the penal or criminal code.

In New Hampshire, as in many states, voluntary intoxication is generally not a defense to criminal charges. This means that if a defendant was under the influence of drugs or alcohol by their own decision, they cannot use that state of intoxication to excuse their criminal behavior. However, if the intoxication was involuntary—meaning the defendant was drugged without their knowledge or against their will—it may serve as a defense if it can be shown that the defendant was incapable of understanding or controlling their actions. New Hampshire law does recognize that involuntary intoxication can negate the requisite mental state required for a crime. Regarding voluntary intoxication, it may be considered by the court in specific cases where the crime requires a particular intent or state of mind, such as specific intent crimes like attempted murder. In such cases, the defendant may argue that due to intoxication, they were unable to form the specific intent necessary to commit the crime. Ultimately, whether intoxication can be used as a defense and its impact on the defendant's mental state is a question of fact for the jury to determine, based on the evidence presented at trial.