The simple answer to the OP's question is that "it depends". The general deer seasons are explicit in what type of deer may be taken, and there are not westside GMUs that allow whitetail deer to be harvested. However, many special permits allow "any deer", "3 pt or better", "any buck", or "anterless deer" without limitations on specie. In these instances, a whitetail could be legally hunted and killed.
Page 81 of last year's regs:
8. Endangered Species:
It is illegal to hunt, possess, or control protected
wildlife or endangered species. Endangered species
are: pygmy rabbit; fisher; gray wolf; grizzly bear;
sea otter; sei, fin, blue, humpback, black right, killer
(orca) and sperm whales; Columbian white-tailed
deer; woodland caribou;.......
Even if your permit says "any deer" you'd better take that to mean antlerless blacktail are included rather than includes whitetail. Or be prepared to prove that the WWA whitetail in your possession is a non columbian species.