Look, I shouldn't have been patronising about the desire for retribution, I agree that it's not going away and I feel it myself sometimes, like for those judges that were taking bribes to give kids tougher sentences. Any penal system that doesn't indulge the public's sense of retributive justice is not likely to last.
But like you say, sentencing goes way beyond 'an eye for an eye' in most cases. Maybe, like you suggest, it takes savagely disproportionate sentences to work as a deterrent. In any case, I agree that prisons are functional to society as it is, and not going anywhere fast, but as shag keeps pointing out, Davis's point is to make a society which is less criminogenic. Anyone can get behind that - even the Blairite slogan is "tough on crime, tough on the causes of crime". But in the meantime, our societies - especially the US - are way tougher on crime than they need to be, and tough on a lot of things that don't need to be crimes. Prisons are hellish and the fact that they are bursting at the seams is for me one of the clearest signals that something is rotten in society as a whole.
As for the relationship between Reagan and crime rates: it fails to explain why Canadian rates fell the same magnitude. Between 1991 and 2001 the ratio of cops to population in Canada fell 9 per cent and the incarceration rate fell 7 per cent, while the American figures moved 10 per cent and _47 per cent_ respectively. Yet most of Canada saw about the same fall in homicides, armed robberies and burglaries as the US. These stats are from Loic Wacquant in Socialist Register 2006, and he gets them from Canadian criminologist Marc Ouimet, whose original article I can't read as it is in French. But according to Wacquant, Oimet argues that the parallel crime rate falls need some explanation that apply evenly to both countries, and "he points towards two exogenous forces... the one-fifth drop in the number of people in the 20- to 34-year age bracket on both sides of their common border, and the marked decrease in unemployment in both countries, which allowed unskilled lower-class youths to find work and thus encouraged them to withdraw from the criminal economy." ["The 'scholarly myths' of the new law and order doxa", pp. 100-01]
Mike Beggs scandalum.wordpress.com