MILWAUKEE (AP) -- Newt Gingrich is calling on federal officials to overhaul the nation's prison system, an issue he knows isn't a typical Republican hot-button topic.

The former House speaker made his comments during a brief stop in Milwaukee on Monday evening.

Gingrich says nonviolent offenders should be given a real chance to rehabilitate, in a prison system that doesn't expose them to gang turf wars and threats of rape.

He says the U.S. shouldn't tolerate barbarism inside walls it theoretically controls.

Gingrich's comments were met with polite applause by the crowd of GOP supporters.

Gingrich attended on behalf of Milwaukee County Executive Scott Walker, who's running for governor in 2010. Gingrich praised Walker but stopped short of a full endorsement.