There are positive benefits from such TV shows, such as
- creating positive role models for our youth,
- encouraging students in the sciences and mathematics,
- educating the public in basic legal and forensic concepts that form the foundation of many investigations and judicial procedings, and
- building support for local law enforcement.
As a matter of public policy, there is a tradeoff between the benefits I listed above and possibly educating criminals, as well as confusing the public by building up unrealistic expectations for the detectives, forensic scientists/technicians, and prosecuting attorneys (a.k.a. solicitors) to have to meet.