In the 1960s, as drugs became symbols of youthful rebellion, social upheaval, and political dissent, the government halted scientific research to evaluate their medical safety and efficacy.
In June 1971, President Nixon declared a “war on drugs.” He dramatically increased the size and presence of federal drug control agencies, and pushed through measures such as mandatory sentencing and no-knock warrants.
A top Nixon aide, John Ehrlichman, later admitted: “You want to know what this was really all about. The Nixon campaign in 1968, and the Nixon White House after that, had two enemies: the antiwar left and black people. You understand what I’m saying. We knew we couldn’t make it illegal to be either against the war or black, but by getting the public to associate the hippies with marijuana and blacks with heroin, and then criminalizing both heavily, we could disrupt those communities. We could arrest their leaders, raid their homes, break up their meetings, and vilify them night after night on the evening news. Did we know we were lying about the drugs? Of course we did.”
Whether the motivation was the "damned hippies" "lawless blacks" or some other bigotry, the timeline of events is not disputed. Even though the health advisers unanimously stated that marijuana is not at all worthy of the Class One restrictions, politicians left it there because it was a convenient way to initiate police powers against suspected malcontents.
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Nixon temporarily placed marijuana in Schedule One, the most restrictive category of drugs, pending review by a commission he appointed led by Republican Pennsylvania Governor Raymond Shafer.
In 1972, the commission unanimously recommended decriminalizing the possession and distribution of marijuana for personal use. Nixon ignored the report and rejected its recommendations.
Between 1973 and 1977, however, eleven states decriminalized marijuana possession. In January 1977, President Jimmy Carter was inaugurated on a campaign platform that included marijuana decriminalization. In October 1977, the Senate Judiciary Committee voted to decriminalize possession of up to an ounce of marijuana for personal use.
Within just a few years, though, the tide had shifted. Proposals to decriminalize marijuana were abandoned as parents became increasingly concerned about high rates of teen marijuana use. Marijuana was ultimately caught up in a broader cultural backlash against the perceived permissiveness of the 1970s.