Exactly correct! But the real question is "Why would he do this?" In my view, it was an attempt to cover up his crime. He knew very well that keeping wild coho was illegal, so he tried to make it appear they were hatchery coho, as absurd as that sounds.

If he had "accidently" bonked two wild coho, and later realized he could not retain them, the only recourse is to return them to the water. I know that doesn't make it legal, but possession is 90% of the law.