Without being ignorant, this fish is dead. I am not implying the OP had caught the fish, but otherwise maybe found the fish or such. But without a doubt, this is a deceased fish. The discolouration on the upper part near the head shows the fading area on the scales, as well as the fishes appearance of being quite stiff with a straight eye, and open jaw.
Secondly, ID wise, the tail is a dead giveaway with the tail rays/calcium deposits, as well the spotting, squareness to the tail. Along with that you get your features throughout the fish that it is without doubt a Steelhead. Spotting on the dorsal, across the body, the lateral line, and near the head.
Rather than trying to stir the pot, this is important information to note for newer anglers who an unaware that by-catches do happen when least expected, and that it is important to know your fish ID, regardless if this fish died of natural causes or was killed. Judging by the proportions of the fish and the time of the year, this was most likely a stray Interior Summer Fish.