The APM is an ass. RAFP have no jurisdiction whatsoever over civilians on or off camp, let alone issue FPNs. If they have to deal with a civilian, they have to call in the local police. Witness what happened when protesters broke into several camps a few years ago [inc the women at Greenham Common] - RAFP couldn't touch them, arrest them or anything.
A plod tried it on me once [off base on a public road] for doing 70 in a 60 zone and stopped me because I was in uniform [blue light, the lot - which is illegal on a public road]. He was extensively rebriefed by the base chief plod soon after.
I would have submitted a formal complaint to OC Admin - that sort of attitude we don't need. The Forces and media are doing a great job turning the tide of public opinion pro Forces. Twits like this bonehead can only serve to damage the perception of the public.
I'd get your friend to write a formal complaint to OC Admin. This pratt needs to be knocked of his high horse of self importance before he does some substantial damage. Make sure he mentions in his letter that he is an ex-policeman.