This week, the Supreme Court made a decision that was somewhat newsworthy: upholding the right of a prison inmate to do something the prison authorities prohibit. What made it really unusual is that the decision was unanimous, with all the conservative justices signing on, and that the opinion was written by one of the most conservative, Samuel Alito.

Alito is not a staunch friend of prison reformers. In a case involving the treatment of inmates in California, he wrote scornfully, “The Constitution does not give federal judges the authority to run state penal systems. Decisions regarding state prisons have profound public safety and financial implications, and the states are generally free to make these decisions as they choose.” Antonin Scalia and Clarence Thomas have been no more sympathetic.