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 South Dakota, as in many states, voluntary intoxication is generally not a defense to criminal charges. This means that a defendant cannot typically claim that being under the influence of drugs or alcohol excuses their criminal behavior or negates their criminal intent. However, there are exceptions where involuntary intoxication may be considered a defense. Involuntary intoxication can occur if the defendant was coerced into consuming the substance or was unaware they were consuming it due to someone else's actions. In such cases, the defendant may argue that they lacked the requisite mental state to commit the crime due to the intoxication. For specific intent crimes, such as attempted murder, a defendant in South Dakota might argue that their voluntary intoxication prevented them from forming the specific intent required for the crime. Whether this defense is acceptable and its impact on the defendant's criminal liability is ultimately a question of fact for the jury to determine. The precise regulations and allowances for intoxication defenses would be detailed in South Dakota's penal or criminal code and interpreted by case law.