During the Prohibition in Canada, which was imposed federally during World War I, overall alcohol consumption may have dropped, but drinking did continue through other outlets; most experts agree the policy was extremely costly in broad societal terms. Canada's first antinarcotics laws were passed in the 1950's to outlaw opium-smoking among Chinese immigrant laborers and were imposed most harshly on street addicts and small-time dealers. Since about 1980, cannabis use and related arrests have been declining in Canada, although statistics still show that most drug crimes are related to cannabis possession. During the 1980's, the amount of cocaine imported in Canada increased dramatically, as in other countries, and interdiction efforts have been ineffective in preventing greater availability and higher purity of cocaine. The criminal law has been ineffectual in preventing drug use because of several factors: offenders believe the risk of arrest is remote, the socializing effects of the law are undermined when all drugs are treated equally beneath it, the law's moral authority is weakened by widespread violations of drug laws with little enforcement, and many people do not accept the basic premise that all drug use is immoral. 2 tables, 1 figure, 6 notes, and 71 references