The common law position in Australia is that evidence of intoxication should be taken into account when determining whether the government has proved beyond reasonable doubt that an accused person acted voluntarily and intentionally. Similar principles apply in individual jurisdictions, although evidence of intoxication is generally relevant only to certain classes of offenses. Many recent legal commentaries on the issue of intoxication and criminal responsibilities have often largely ignored the vast and rapidly growing scientific literature on the nature and effects of intoxication. The psychoactive drugs can be grouped according to their major pharmacological properties. The categories include central nervous system depressants, central nervous system stimulants, opiates, cannabis, hallucinogens, and anabolic steroids. The research literature suggests that the effects of intoxication on criminal behavior may vary greatly depending on the type of drug and a number of situational factors. Therefore, blanket principles do not appear appropriate to deal with the law on intoxication and criminal responsibility. Instead, each case of intoxication should be considered separately to determine whether the accused person’s behavior was likely to be a consequence of intoxication. 94 reference notes (Author abstract modified)