Delta 8 THC is not legal according to Washington state law. But Delta 9 THC is legal.
Why is delta 9 THC legal? read more HERE
(f) “Controlled substance” means a drug, substance, or immediate precursor included in Schedules I through V as set forth in federal or state laws, or federal or commission rules, but does not include hemp as defined in RCW 15.120.010.
(x) “Marijuana” or “marihuana” means all parts of the plant Cannabis, whether growing or not, with a THC concentration greater than 0.3 percent on a dry weight basis; the seeds thereof; the resin extracted from any part of the plant; and every compound, manufacture, salt, derivative, mixture, or preparation of the plant, its seeds or resin. The term does not include:
(1) The mature stalks of the plant, fiber produced from the stalks, oil or cake made from the seeds of the plant, any other compound, manufacture, salt, derivative, mixture, or preparation of the mature stalks (except the resin extracted therefrom), fiber, oil, or cake, or the sterilized seed of the plant which is incapable of germination; or
(2) Hemp as defined in RCW 15.120.010.
(tt) “THC concentration” means percent of delta-9 tetrahydrocannabinol content per dry weight of any part of the plant Cannabis, or per volume or weight of marijuana product, or the combined percent of delta-9 tetrahydrocannabinol and tetrahydrocannabinolic acid in any part of the plant Cannabis regardless of moisture content.
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