It has escaped the notice of Alito that the state can protect the public from such felons without holding them in prison -- using electronic monitoring, drug testing and strict supervision to keep them on the straight and narrow.
"I don't think there's any doubt that we can let out more than 30,000 prisoners and have crime go down, if we spend some of the money we save by not housing them on watching them better in the community," UCLA criminologist Mark Kleiman said in a radio interview.
GPS surveillance of a felon costs about $4 a day, he points out -- a massive bargain next to the $100 a day needed to house and feed him in prison. If the function of penitentiaries is to keep bad people from preying on good people, it often can be achieved just as well with newfangled technology as with steel bars and razor wire.
Many legislators have already stumbled on a way to spend less and be more secure: lock up fewer people. States from New York to Texas have decided that mass imprisonment is a luxury they have to curtail. Marc Mauer, head of The Sentencing Project, reports that in the states that have cut back on incarceration, "no adverse impacts on public safety were observed."
In the long run, locking up so many criminals is a false comfort. It may be no coincidence that California has an unusually high rate of recidivism. The former warden of San Quentin State Prison testified that existing prison conditions "make people worse." Most of those people wind up back among us, more dangerous than before.
Cramming ever-growing numbers of offenders into horribly overburdened facilities is an inexcusable way to treat the guilty. And guess what: It's no favor to the innocent.