A History of U.S. Drug Enforcement

For most of the nineteenth century, the United States barely regulated drugs at all. Opium, morphine, cocaine, and cannabis were legal, sold in pharmacies and patent medicines. The system of enforcement Americans know today was built in roughly a century of statutes — each a response to the moment, and each shaping the one that followed.

The first federal laws (1906–1937)

The Pure Food and Drugs Act of 1906 was an early milestone in federal drug regulation. It prohibited interstate commerce in adulterated or misbranded drugs and required labels to disclose the presence and amount of certain dangerous or habit-forming substances, including alcohol, heroin, and cocaine. The Harrison Narcotics Tax Act of 1914 went further, imposing federal registration, recordkeeping, taxation, and prescription requirements on opium and coca products and becoming a foundation of federal narcotics enforcement.

The Marihuana Tax Act of 1937 used a tax-and-registration system to sharply restrict marijuana transactions. Federal narcotics enforcement was led by the Federal Bureau of Narcotics, created in 1930, whose first commissioner, Harry Anslinger, remained in charge until 1962 and became highly influential in U.S. drug policy.

The Controlled Substances Act (1970)

The modern framework arrived with the Controlled Substances Act of 1970, which replaced the patchwork of earlier laws with a single system of five "schedules" ranking drugs by accepted medical use and potential for abuse. Schedule I is the most restrictive category and is defined by federal law as applying to substances 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. These classifications continue to affect how controlled substances are regulated, researched, manufactured, distributed, and prosecuted. In 1973, the Drug Enforcement Administration was created to enforce it.

The war on drugs (1971–1990s)

In June 1971, President Richard Nixon described drug abuse as "public enemy number one" and called for a major federal offensive against it, a moment commonly associated with the beginning of the modern "war on drugs."

Federal drug enforcement expanded substantially during the 1980s. The Anti-Drug Abuse Act of 1986 established mandatory minimum penalties for certain drug offenses and created a 100-to-1 disparity between crack and powder cocaine thresholds: five grams of crack cocaine and 500 grams of powder cocaine triggered the same five-year federal mandatory minimum sentence. The disparity was widely criticized for its unequal racial impact.

Drug-prevention efforts also expanded. Nancy Reagan's "Just Say No" campaign became a prominent public message, while D.A.R.E., established in 1983, spread rapidly through American schools and was operating in all 50 states by the mid-1990s.

Drug arrests, prosecutions, and incarceration increased dramatically during this era. Federal and state data show particularly large increases in imprisonment for drug offenses. At the same time, illicit drug use persisted and changed over time, leading to growing debate over whether criminal enforcement alone could effectively address substance use and addiction.

The turn toward treatment (2010–today)

The correction came slowly. The Fair Sentencing Act of 2010 reduced the crack-to-powder disparity from 100-to-1 to 18-to-1; the First Step Act of 2018 made parts of it retroactive. As the opioid overdose crisis deepened, federal policy increasingly framed addiction as a treatable health condition rather than a purely criminal one — expanding access to medication-assisted treatment, funding the overdose-reversal drug naloxone, and standing up new crisis-response infrastructure. The enforcement machinery of the last century still stands, but alongside it a different premise has taken hold: that people with substance use disorders recover through care, not punishment.