"He said he released the turtle."
So you're right: No turtle, no identification by qualified biologists, no testing to determine if the putative turtle had actually traversed Mr. Maier's land.
...you have people who have a certain point of view acting on behalf of the state without supervision...
Yes, and since when does the state fund the defense of a self-appointed "volunteer" for the state?!
If a "volunteer" turns in his neighbor for, say, child abuse; and then the allegation begins to look false and maliciously motivated, is that volunteer's defense going to be paid by the taxpayers when he is sued for defamation by the accused? I doubt it.
The state is providing a defense because they have a policy of recruiting and directing volunteers to do exactly what Mr. Argus was doing. It was not that he was a passerby who happened to see something. He was acting at the direction of the state as an unpaid volunteer. This crucial difference is why the state is interested in defending him.
I think this is the wrong decision. I also think it is wrong for the state to use unpaid volunteers to gather information, because this system invites just this type of abuse. The whole system should be scrapped, and the Audobon Society can just have tough noogies.