By "Criminal University" I assume they are referring to the phenomenon of a person going to prison for something minor, e.g. like stealing a bike, and coming out with intimate knowledge of how to commit more serious crimes.
In that case, yes, it's a real phenomena. People go in for minor things. They make contacts (network). After release many have no (real) alternative but to participate in criminal activity since they cannot find a job due to their background check.