“Does a government agency have the legal authority to do this?”
Seattle would seem to have the State Supreme Court in their pocket.
Not surprising at all.But consider this...a year or so ago SCOTUS accepted a 2nd Amendment case from the Massachusetts Supreme Court called "Caetano v Massachusetts".Long story short SCOTUS ruled,9-0,that the state's Supreme Court issued a "frivolous" ruling in upholding Ms.Caetano's conviction on a gun possession charge stating that the ruling was in direct defiance of the recent Heller and Chicago rulings.
So any ruling issued in Olympia (the state's capital?) could very well be blown out of the water in DC.