Tucker, I believe, was in the Air Force, and Adams was a cop. It is clear that Adams took the first shot at Tucker's plain, most likely due to shock and sudden reflexes. The firing from plane was unexpected to the men on the ground, and Adams did the first thing that he could think of. Somebody else also shot Tucker's plane. It was clearly self defense, but since Tucker had some clout, it could be taken differently.
shareA three year late reply is probably pointless, but I'll give it a shot.
It depends on whether or not they told anyone. Millen and Alvin were the two shooters, and at that point they were pretty much the only one's left other than Lauter, who wasn't in the scene. In his report, Edgar would have to decide what to say about the incident. Since he didn't bury Sundog or bring him with them, there would be no body; no evidence that Tucker had shot him, and therefore no evidence that the mounties had a reason to shoot him down. I would GUESS - and it's just that, a guess - that Edgar would just say that the pilot crashed his plane, and that's it. Alvin wouldn't disagree or rat him out, and Lauter's character (assuming he survived that shot to the leg) probably wouldn't either.
Here's to the health of Cardinal Puff.