The state-trooper detectives did not think highly of the FBI agents and referred to them, behind their backs as the "Fan Belt Inspectors."

No-one likes anyone invading their turf, Father Steve.

It seems to be a "natural reaction" to outsiders, whatever their level of competence.

It's a staple of every cop movie including the one now playing with Angelina Jolie in the title role*, an FBI agent who picks up all the clues the local guys keep missing.

I'm sure the "Fan Belt Inspectors" just went about their business solving the crime ... just like Angelina Jolie.

*"Taking Lives"
Synopsis: When Montreal detectives ask for an outsider's help to get inside the head of a cunning serial killer, top FBI profiler Illeana Scott (Angelina Jolie) joins the case.

http://movies.yahoo.com/movies/feature/takinglives.html

I think the Montreal cops are being a bit pig-headed myself. I'd love to have Angelina Jolie on my squad, even if she was only a "Fan Belt Inspector".

The "Fan Belt Inspection Patrol" would become every inspector's favorite duty. That's what I suspect.