Me personally I think the rank of detective for major crimes IE: Murder, Large robbery, and drug rings. The role of detective would be very boring when these things are not going on due to great police work done by all involved (We all have quite times right lol). So in theory a detective would accept or deny a case depending on the case report from the patrol officer. If the detective thinks the case is valuable enough to dig in further he/she can do so if not they decline and case closed. At another aspect I would like to see detectives also act as prosecutor, keep their job busy right? These are just ideas my military police experience is vastly different from civilian law enforcement so just some thoughts and ideas.