the penalty is a maximum of 15 years. The is something called "Sicherheitsverwahrung" - meaning "keeping for security (of society)". In that case the criminal s

the penalty is a maximum of 15 years. The is something called "Sicherheitsverwahrung" - meaning "keeping for security (of society)". In that case the criminal served his sentence but is still locked up because he is considered dangerous for society. But because it's officially not a punishment anymore they have to be treated less harshly, with more comfortable cells etc.