The ACLU has a sobering infographic on incarceration statistics. A detail:
Eric Sterling explains how the Anti-Drug Abuse Act of 1986 came into being:
At the time, the Senate was controlled by Strom Thurmond and the Republicans. They looked at it and said: "OK, well if the Democrats have a sentence of five years to 20 years, let's up it to 10 years to 40 years. And if the Dems say 20 grams, we’ll make it 5!” Nobody looked at the proper ratios based on how harmful it was. It was completely detached from science. Nobody could say that crack was 100 times more dangerous than powder.
The Dish 