Possession of drug paraphernalia in Washington State is a Misdemeanor and is punishable by a mandatory minimum of 1 day in jail and a minimum fine of $250.00. The maximum penalty for possession of drug paraphernalia is 90 days in jail and a $1,000.00 fine.
For conviction, the prosecutor must prove that you used the paraphernalia in conjunction with a controlled substance.
This can be shown by the presence of drug residue, proximity to certain drug related items (i.e., small zip-lock baggies, large amounts of cash, scales, etc.), or proximity to a controlled substance (i.e., a pipe located next to a bag of marijuana).