It's about catching criminals, but the stories are told from the point of view of the criminal mind of the alleged perpetrator as well as the detectives trying to solve the crime.
Post-mortems are often quite grisly, and there are lots of dead bodies. Guns go off frequently.
Some crimes are sexually based.
Of the three Law & Orders, this show has the mildest language.
Occasionally a cigarette is smoked or a drink or drug consumed.