The problem is, if he did, then he'd be on shaky ground in terms of protecting the IDs of all other FReepers. Whereas, with a subpoena, he can in the future, fight any claims that a precedent was set, in instances where the press or even governments try to find FReepers IDs without subpoenas. It's best to err extremely on the side of privacy.
All of this could be resolved if someone would just follow through with the investigation and start issuing subpoenas. I'm certain their trouble would result in one heck of a damaging story about the local corrupt democrats or local corrupt media.