It's happened! They ended up having to get a restraining order against him.
"Yet, far from succeeding, Monteilh eventually so unnerved Orange County's Muslim community that that they got a restraining order against him. In an ironic twist, they also reported Monteilh to the FBI: unaware he was in fact working undercover for the agency."
What a great read; thanks for posting it. While the reported outcome differed from the Rolling Stone article, the FBI's modus operandi appear the same.
"Yet, far from succeeding, Monteilh eventually so unnerved Orange County's Muslim community that that they got a restraining order against him. In an ironic twist, they also reported Monteilh to the FBI: unaware he was in fact working undercover for the agency."
-- http://www.guardian.co.uk/world/2012/mar/20/fbi-informant