I will take a couple of them. The ones that I think are more appropriate to Professor Doob, I might pass on.
On the Levitt question, I'm actually equally as staunch a critic of Steven Levitt as is Professor Doob. And no, I don't believe any other work exists. In fact, I believe there's really a common thread of disingenuousness through his work, and it's been exposed frequently, by Mr. Doob today, as well as by some others.
On the incapacitation issue--and Professor Doob will probably expand on this--incapacitation has an impact if you take somebody out, but we're talking about already having stiff sentences that exist. That person is already being incapacitated. So the question is, is this a mandatory minimum in some sort of way? Is this going to result in somebody being incapacitated for a longer period of time? In most cases, if you have stiff sentences that exist, that's not going to be the case. In particular, as far as drug crimes are concerned, we've seen that incapacitation really has no effect whatsoever, whether it's for a short period of time or not.
The sentencing issue leading to an increase in crime from 1960 to 1992.... I haven't seen any research leading to that, but I have seen a new strain of research that's emerged since 2000, that's looking at the formation of social control, at informal means of control in social capital within low-income communities where there's high-density incarceration. It has actually been demonstrated in a number of American cities, in a number of different contexts, that there's a tipping point. When incarceration rates reach a certain point within some of these communities--and there are neighbourhoods in American cities where up to one-fifth of the young males in that neighbourhood are incarcerated or in the criminal justice system on any given day--there's a tipping point, and we actually begin to see crime rates increase. It's speculation, and that is as a result of an erosion, really. In any sort of neighbourhood, the constant disruption of people moving in and out of the criminal justice system actually has what would be called statistically a positive effect leading to an increase, which is actually a negative effect.