Jake tells me

My friend Jake got back to me with his initial thoughts on mandatory minimums.

The first thing to understand is that prosecutors love them. So, the Attorney General and, by extension, his posse of prosecutors, are going to call for them. They do this because they like to win, and by win I mean put people away for long periods of time. That these laws incur massive expenditures, disrupt communities and families (although it's naive to think that these communities and families are doing well in any case) and have an unclear relationship with crime is apparently not of utmost concern to them. Practioners particularly those in the field of criminal justice, seem to be unusually disconnected from research on outcomes.

My understanding (not a great one) is that most serious people think that mandatory minimums have at least some deterrent and incapacitory affect. How much affect and compared to what?

A day later Jake sent me citations for research on mandatory minimums in response to drug offenses, as well as a few select quotes:

"The main effect of imprisoning drug sellers, we believe, is merely to open the market for another seller. The market for the illicit drugs has not been disrupted by increased incarceration."

"The drug war might have achieved more if less emphasis had been placed on giving very long sentences."

The citations that he sent me were RAND's "How Goes the 'War on Drugs'?" and the Manhattan Institute's "Right Sizing Justice" (which, Jake pointed out, are not "notoriously liberal").

Jake summed things up by saying

At least with regard to drug offenses, mandatory minimums seem to be more or less panned in the research literature. Keep in mind that drug offenders represent a significant portion of both state and federal prisons and an even more significant portion of recent increases in American prisons.