At 10:10 on the morning of October 27, 1970, Richard Nixon sat at a desk in the Washington offices of the Bureau of Narcotics and Dangerous Drugs and signed a bill he said he had requested 15 months earlier. Attorney General John Mitchell and the bureau's director, John Ingersoll, stood behind him. In his brief remarks the President talked about street crime, heroin, barbiturates and amphetamines, and then put his name to Public Law 91-513, the Comprehensive Drug Abuse Prevention and Control Act.

He did not mention LSD. He did not mention mushrooms, peyote or mescaline. Yet Title II of that law, the Controlled Substances Act, is the reason those substances have spent more than half a century in the most restrictive category in American drug law, a category whose defining claim is that a drug has no accepted medical use at all.

A filing system for every drug

The act was first a consolidation. In 1969 Nixon announced that Mitchell was preparing a single statute to replace the tangle of existing federal drug laws. White House counsel John Dean, Ingersoll, and Michael Sonnenreich, later executive director of the Shafer Commission, helped write it. As introduced in the Senate by Everett Dirksen, the bill ran to 91 pages.

Its central invention was a ladder of five schedules. Where a substance sat on the ladder decided who could make it, who could prescribe it and how hard its misuse would be punished. Schedule V held things like cough medicines with small amounts of codeine. Schedule I, at the top, was reserved for drugs with a high potential for abuse, no currently accepted medical use in treatment in the United States, and a lack of accepted safety for use under medical supervision. No prescription may be written for a Schedule I drug, and production is held to quotas set by federal enforcers.

Congress did not leave the first sorting to scientists. The statute itself created the initial listing, and the hallucinogens went to the top rung. LSD, mescaline, peyote, psilocybin and psilocin, and DMT all sit in Schedule I alongside heroin. LSD was already a named target. The act's definitions, still in force, single out "lysergic acid diethylamide" by name, next to barbiturates and amphetamine, in describing what counts as a depressant or stimulant substance.

How the psychedelics got there

In the mid 1960s Ken Kesey and the Merry Pranksters staged their Acid Tests, LSD parties that moved from the San Francisco Bay Area to Los Angeles, Portland and eventually Houston, often with the Grateful Dead playing. California outlawed LSD on October 6, 1966, and in October 1968 Congress made its recreational use a federal crime. That same year the Johnson administration folded several drug agencies into the new Bureau of Narcotics and Dangerous Drugs. PBS Frontline's timeline of the period describes recreational drug use becoming fashionable among young, white, middle-class Americans in the late 1960s, and becoming a sign of protest.

By 1970 the psychedelics had a reputation and no defenders. A 2026 study in the journal Contemporary Drug Problems, examining how the same substances came under international control, found that despite limited scientific evidence of public health dangers, alarm was amplified by sensationalized media and by the drugs' association with youth counterculture. Alcohol, tobacco, sedatives and stimulants all had cultural, political or economic advocates. Psychedelics had none.

Gentler than its reputation

The act is now remembered as the opening shot of the drug war, but in 1970 it could be read another way. Frontline notes that it reduced penalties for marijuana possession, even as it let police conduct "no-knock" searches. The historian David Courtwright called it part of a package designed "to rationalize, and in some respects to liberalize" American drug policy. It eliminated mandatory minimum sentences and funded treatment and research, provisions added as a compromise with Senator Harold Hughes, who favored a moderate approach. It also created a national commission on marijuana, chaired by the former Pennsylvania governor Raymond Shafer, which in 1972 recommended decriminalizing possession of small amounts. The recommendation went nowhere.

Nixon's own remarks fit that mixed picture. He promised more than 300 new agents and federal reach over pills as well as heroin, but he also said that a person hooked on drugs is "one that we must have sympathy for," and described a new national treatment program.

The tone hardened quickly. On June 17, 1971, Nixon named drug abuse "public enemy number one in the United States." Even then, Frontline points out, the Nixon years were the only period of the drug war in which most federal funding went to treatment rather than law enforcement. In July 1973 the narcotics bureau and other agents were merged into the new Drug Enforcement Administration.

Abroad, psychedelics came under the Convention on Psychotropic Substances, signed in Vienna on February 21, 1971. The archival study found a twist there: the United States preserved room for psychedelic research and the use of psychedelic plants, against French and Soviet proposals for tighter control.

The quote everyone cites

Any account of the 1970 law now runs into one famous remark. In 1994 the journalist Dan Baum interviewed John Ehrlichman, Nixon's former domestic policy adviser, who told him the Nixon White House "had two enemies: the antiwar left and black people." By linking hippies with marijuana and black Americans with heroin, Ehrlichman said, the administration could arrest leaders, raid homes and disrupt both communities. Baum published the exchange in Harper's in 2016.

It is a damning statement and it may well be candid. It should still be weighed for what it is: one aide's recollection, reported by one journalist, printed more than two decades after the conversation. It names marijuana and heroin, not LSD, and it speaks to the political drug war of the early 1970s rather than to a statute shaped by treatment provisions and Senate bargaining. The paper trail supports neither a pure public health reform nor a pure conspiracy.

Easy in, hard out

What has lasted is the machinery. Under section 811 of the act, anyone from a drug company to a private citizen can petition to move a substance between schedules. Before acting, the Attorney General must obtain a written scientific and medical evaluation from the Secretary of Health and Human Services, which binds him on scientific and medical matters. If the Secretary says a drug should not be controlled, it cannot be.

The top rung has proved sticky. The act never defines drug abuse, and the Drug Enforcement Administration reads it so that a drug need not be as abusable as heroin to stay in Schedule I. If it has no currently accepted medical use and some potential for abuse, it must remain. For a substance no doctor may prescribe, an accepted medical use is hard to establish. When the DEA moved MDMA into Schedule I in the 1980s, its own administrative law judge ruled twice that the placement was illegal, and the drug was briefly unscheduled from December 22, 1987, to July 1, 1988. It went back anyway. The law's exceptions are narrow and religious: peyote for Native American churches, and DMT in ayahuasca for the UDV church on religious freedom grounds.

More than five decades on, LSD, psilocybin and mescaline remain where a 91-page bill placed them, in a schedule that says they have no accepted medical use, under a law whose signing remarks never named them once.