The Path to Prohibition — How Cannabis Became Illegal (1900–1937)
Racial panic, bureaucratic ambition, ninety-two seconds of House debate, and the AMA opposing a bill that a congressman lied about them supporting. The real story of how cannabis became illegal.
The criminalization of cannabis in the United States was not a rational response to new pharmacological evidence. The plant had been in the U.S. Pharmacopoeia since 1850. Roughly 280 American manufacturers produced more than 2,000 cannabis-containing medicines. What changed was not the science but the politics — and the politics were built on race, bureaucratic survival, and a press ecosystem that sold panic for circulation.
This section traces that path from the first state bans through the Marihuana Tax Act of 1937, evaluating both the historical consensus and the popular conspiracy theories that have grown up around it.
The chapters
The First State Bans
Massachusetts 1911, not El Paso 1914. The corrected chronology that demolishes the standard story — and the Mormon myth debunked by Ardis Parshall.
Read →"Marihuana"
The AMA's Dr. Woodward called it "a mongrel word." The deliberate rhetorical strategy of using an unfamiliar Spanish-derived name to obscure the drug's medical identity.
Read →Anslinger & the FBN
32 years, five presidents. How a Prohibition-era bureaucrat reinvented his agency around marijuana after alcohol was re-legalized in 1933.
Read →The Gore Files
The Victor Licata case, planted newspaper stories, racial framing — and what Anslinger actually said vs. the viral quotes that cannot be verified in primary documents.
Read →The Tax Act of 1937
Two hours of hearings. Ninety-two seconds of floor debate. The AMA opposed it. A congressman lied and said they supported it. FDR signed it anyway.
Read →The Herer Conspiracy
Hearst, DuPont, Mellon, and Anslinger — the most influential conspiracy theory in cannabis history. What it gets right. Where it collapses. Why the chronology is fatal.
Read →Propaganda Films
Reefer Madness, Marihuana, Assassin of Youth — the exploitation film cycle. Plus the surprise: Anslinger tried to suppress Reefer Madness.
Read →Key dates
Massachusetts bans cannabis
The first US state ban — four years before El Paso, in a state with virtually no Mexican-American population. Driven by Protestant moral-reform networks.
Mexico bans cannabis nationally
Seventeen years before the US Marihuana Tax Act, for reasons having nothing to do with Hearst or DuPont.
Federal Bureau of Narcotics created
Harry Anslinger appointed founding commissioner by Treasury Secretary Andrew Mellon.
Prohibition ends — FBN needs a new mission
Anslinger pivots from treating cannabis as a regional nuisance to building a case for federal action.
Reefer Madness released
An exploitation film, not official FBN propaganda. Anslinger later tried to suppress it.
Marihuana Tax Act signed
Signed by FDR on August 2, effective October 1. Two hours of hearings. AMA opposition overridden with a lie on the House floor.
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