. . . in the end, the federal government has very little control over criminal justice. About 90 percent of all prisoners—and a far greater percentage of those in jails, on probation, or who are arrested every year—are handled by states and counties, not by the federal government. And the federal government cannot directly tell states what to do when it comes to dealing with these individuals. For example, they cannot make local governments change their laws, enforce existing laws more aggressively, or determine who is released on parole or who is sent back to prison.
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