The court held that the definition of conspiracy within the Washington Criminal Code allows for a conviction when the other party to the conspiracy is a law enforcement officer or other government agent who did not intend that a crime be committed – applies to a conviction for conspiracy to distribute methamphetamine. Thus, the statute criminalizes conduct not criminalized by the federal conspiracy statute, and as such, is overbroad as compared to generic definition of a controlled substance offense.
The decision in US v. Brown can be found here:
http://cdn.ca9.uscourts.gov/datastore/opinions/2018/01/16/16-30218.pdf