The standard answer, of course: Ronald Reagan.
But, as it turns out, there is plenty of credit to share in this matter.
Maya notes that, in fact, it was not President Reagan "behind the gross disparities in sentencing of cocaine traffickers but in fact the liberals who created the problem in the first place." Indeed, in 1986, as Congress was drafting the Anti-Drug Abuse Act, mandatory sentencing minimums for trafficking in crack cocaine and powder cocaine were treated differently, "based on presumptions about the degree of differences in the addictiveness of crack cocaine and its link to violent behavior."
The person responsible for the crack-powder cocaine ratio contained within the Anti-Drug Abuse Act of 1986 was Vice President Joe Biden. Then-Senator Biden succumbed to what he later referred to as “a feeling of desperation” and proposed a 100-to-1 ratio. His Democratic colleague from Florida, Senator Lawton Chiles, went even farther, by suggesting a 1000-to-1 ratio. The 100-to-1 ratio ultimately became law and served as the basis for the November 1, 1987 sentencing guidelines. By contrast, the Reagan administration proposed a much more reasonable 20-to-1 crack-powder ratio.The Editor of PardonPower has read a hundred articles on this topic, but has never once seen this information before. Somewhat amazing, is it not? Now, two decades later, Biden admits that his idea was "wrong" because it is "unfounded and unfair” and based on "myths." The Fair Sentencing Act of 2010 has reduced the ration to 18-to-1. But we have yet to hear of Biden interceding on behalf of a single individual punished by his Draconian measures. Regardless, President Obama should reinforce the sense of conviction that drove him to sign the recent Act into law by using the pardon power. See article here.