by the end of his visit, wetzel was buying it.started implementing some of the things he saw in germany, like more intensive staff training, greater freedom for inmates with good behavior and programs to help them re-enter society. we, the american public, called for tougher sentencing, throwing away the key. are we there for this more lenient approach? >> wetzel: i think our culture, we don't want to think lenient. we don't want to think soft. we got here by being tough on crime. i think we're getting away from it by being smart on crime, and smart on crime happens to be more lenient. >> whitaker: sometimes, germans think their prisone but the system is mandated and protected by the country's highest court. there are problems. they have gangs. they have drugs. they've seen signs of islamic radicalization. they try to counter it all with counseling. but there are inmates deemed too dangerous to release. they wind up in something called preventive detention. at berlin's tegel prison, we met chris templiner. he has spent the last 18

. >> john wetzel is pennsylvania secretary of corrections. three years ago he want to germany looking for ideas to improve his prisons. he showed us around graterford outside philadelphia. largest maximum security prison in pennsylvania. 3,300 prisoners are packed in here. we were walking through block, people dying in the ces, you smem the wau smell the water. >> you are preaching to the choir. >> ain't nothing but poor, black, latino people in the jail. it's bad in here, man. it's bad. >> wetzel started as a prison guard three decades ago. back in 1980, there were 8,000 inmates in the state. today there are 50,000. physical and sexual assaults are a fact of life. at graterford there are more than 700 lifers. >> pennsylvania is a state where life means life. if you are doing life here, you are not going to be walking around a park, eating sundaes with your family. >>> you can see the full report on our website, cbsnews.com. the "cbs overnight news" will be right back. >>> executives from several major corporations including pepsi, levis and