Congress expanded mandatory minimums during the War on Drugs. The Anti-Drug Abuse Act of 1986 set five- and ten-year minimums based on drug quantity. It treated crack cocaine 100 times more harshly than powder cocaine, so 5 grams of crack triggered the same five-year term as 500 grams of powder. Crack prosecutions targeted mostly Black defendants.
Because judges cannot go below the minimum, prosecutors decide the sentence when they choose what to charge. Many states passed their own mandatory minimums in the 1980s and 1990s, fueling mass incarceration.
The Fair Sentencing Act of 2010 reduced the crack-to-powder ratio to 18 to 1. The First Step Act of 2018 made that change retroactive and eased some other federal minimums. Many mandatory minimums remain on the books at the federal and state levels.