Today's Houston Chronicle features this op-ed from Eric Sterling, a/k/a the man who was there at the beginning, when Congress created our current mandatory minimum drug laws (including those for crack cocaine) back in 1986:
I was the assistant counsel to the House Judiciary Committee assigned to help the committee get the numbers right, but we failed. Congress picked different quantities for various drugs to identify drug traffickers who would get at least five years, and up to 40 years, in prison - 100 grams of heroin, 10 grams of pure PCP, one gram of LSD, 500 grams of cocaine powder and five grams of crack cocaine. Larger quantities, such as 5,000 grams of cocaine powder or 50 grams of crack cocaine, get a mandatory sentence of 10 years and up to life in prison. Obviously, in the world of major league cocaine traffickers who smuggle tons of cocaine (a metric ton is 1 million grams), these are trivial quantities.