In a prosecution under 18 USC section 922(g)(3) for possessing a firearm while being an unlawful user of marijuana in which the defendant's conditional guilty plea reserved for appeal the question of whether his conviction violates his Second Amendment right to keep and bear arms, judgment of conviction is reversed, where: 1) intermediate scrutiny is the appropriate standard for review of the statute; 2) Congress had an important objective for enacting the statute to reduce gun violence, and disarming drug users and addicts might reasonably serve that objective; but 3) the government did not present sufficient evidence to substantiate the fit between its objective and the means of serving that objective.