Technically, yes. The consumption of both cat and dog is still legal in 44 states, including Washington. However, this only applies to personal consumption. Restaurants are prohibited from selling dog or cat meat by law, and slaughterhouses are also prohibited from killing cats or dogs to sell as commercial meat. Killing a dog or cat on one's own time, for personal consumption, is still unfortunately legal.
HOWEVER
A bill is currently being passed that would prevent the consumption of both cat and dog meat in all states, as of September 13, 2018. Although the bill has not yet been passed, officials say they are confident the bill will make it through.
Currently, it is still legal to eat a cat, just not in a restaurant.
