It could happen here:
The Supreme Court, in a narrow 5-4 decision, has an upheld an injunction by a three-judge panel ordering California to release about 46,000 inmates -- more than one-fourth the state prison population -- over the next two years to relieve overcrowding.
The decision was written by Justice Anthony Kennedy and backed by the court's liberal bloc. At issue was whether federal judges had the power to order the release of state prisoners as a necessary means of curing a constitutional violation.
Things aren't as bad here as they are in California (is any issue in any state as bad as it is in California?), but prison overcrowding has become an issue. Unless legislators can be persuaded to fund more prison space (doubtful) or state officials can find a way to ease county prosecutors' "soft on crime" concerns about prison reform (possible), we're headed for a showdown. The sudden release of thousands of criminals wouldn't exactly be tough on crime.