How Common Is It for Law Enforcement to Work With Psychics?

Most departments, 99% of them that I've come across have worked with a psychic in some capacity. They just don't put it out there. One is, you know, the old fashioned Google factor is still alive. The other thing is they don't want to be perceived as as a friendly as we call them the friendlies. So what do in your experience, what do police departments not want from psychics?