How would he know where spy cameras are? By definition, they are hidden. Many people have them.
Anyway, if you are considering cameras, get at least one that doesn't really look much like a camera (no green light while filming), hide at least one, etc. Some are very small and would be very hard to find (inserted between books on a shelf, hidden in a photo frame, etc). Even better, have a system that uploads automatically to the Cloud so that the last image it captures is the face/body of the perp. I realize this isn't possible for everyone - but universities should, perhaps, consider it.