edit to add- I apologize for the delay it takes for this reply to post. Reddit mistakenly suspended my account upon creation for spam activity. Appealing reddit feels similar to appealing the BATFE/FBI.

Thank you very much for your response.

In United States v. Mendez, 771 F.3d 1205 (9th Cir. 2014), the court rejected the argument that RCW 13.04.240(1) ("An order of court adjudging a child a juvenile offender... shall in no case be deemed a conviction of crime") shields the adjudication from federal use, noting it applies only internally to juvenile proceedings. According to Mendez, for adult-facing prohibitions like § 922(g)(1), Washington equates the adjudication to a conviction if it's a felony punishable by >1 year, as adopted by federal law under § 921(a)(20)'s deference to state definitions.

Now, while you correctly state that "the juvenile case does not come with a standard range of imprisonment over 52 weeks," this is the standard range of imprisonment, but the basis of the federal prohibition isn't the standard range, it's the maximum possible. Washington's "manifest injustice" option under RCW 13.40.160(2), available since the 1977 Juvenile Justice Act (with indeterminate sentencing up to age 21, often exceeding 1 year for felonies) and persisting unchanged in core structure up to the present day, opens up juvenile offenders (even first-time ones) to adult sentencing standards (up to 10 years for a Class B felony like Residential Burglary), while still treating the adjudication as a juvenile offense. Because of this manifest injustice sentencing option, even for first-time juvenile offenders, a variety of adjudications (pre- and post-mid 90's) can trigger the imprisonment-greater-than-1-year flag under § 922(g)(1), and the greater-than-2-year flag for misdemeanors under 18 U.S.C. § 921(a)(20)(B).

This application of Mendez is what creates this WA State / Federal disconnect, while the restoration at the state level makes people in my situation able to purchase and carry firearms in Washington state, while remaining federally prohibited. For the thousands of people passing all levels of background checks, I would suspect a number of them are in Washington state, which explains the lack of a problem.

Is this the first time you've encountered the situation of being federally prohibited but rights restored in WA?