The statute is 18 U.S.C. § 922(g)(3), which bans possession by anyone "who is an unlawful user of or addicted to any controlled substance (as defined in section 102 of the Controlled Substances Act." The case is U.S. v. Yancey (W.D. Wis. Oct. 3), and the relevant analysis is:

As this court noted recently, Heller stands only for the proposition that the District of Columbia cannot constitutionally ban handgun possession in the home for use in self-defense by persons not otherwise prohibited from gun possession. United States v. Kilgore, 2008 WL 4058020 (W.D. Wis. Aug. 26, 2008). Heller did not address a state’s right to impose restrictions on handgun possession. Indeed, the Court said explicitly that its opinion was not intended to suggest that all gun laws and firearms restrictions are unconstitutional. Id., at 2816-17 ("[N]othing in our opinion should be taken to cast doubt on longstanding prohibitions on the possession of firearms by felons and the mentally ill ...["]). As this court held recently in affirming the constitutionality of 18 U.S.C. § 922(g)(1), which criminalizes firearm possession by felons, Heller did not make the firearm restrictions of 18 U.S.C. § 922(g) constitutionally suspect. Instead, this statute contains just the sort of longstanding prohibitions on firearm possession that Heller allowed. Kilgore, 2008 WL 4058020.

Since Heller was decided, no court has found the firearm restrictions in 18 U.S.C. § 922 to be unconstitutional, even under an individual rights interpretation of the Second Amendment. Instead, courts have repeatedly affirmed the constitutionality of the statute’s prohibition of firearm possession by felons, E.g., Kilgore, 2008 WL 4058020; United States v. Robinson, 2008 WL 2937742 (E.D. Wis. July 23, 2008); U.S. v. Brunson, 2008 WL 4180057 (4th Cir. Sept. 11, 2008); United States v. Irish, 2008 WL 2917818 (8th Cir. July 31, 2008); United States v. Gilbert, 2008 WL 2740453 (9th Cir. July 15, 2008)); persons convicted of domestic violence offenses (United States v. Booker, 2008 WL 3411793 (D. Maine Aug. 11, 2008); United States v. White, 2008 WL 3211298 (S.D. Ala. Aug. 6, 2008)); and illegal aliens (United States v. Boffil-Rivera, No. 08-20437(S.D. Fla. Aug. 12, 2008)). Although to my knowledge no court has confronted the provision defendant challenges, which prohibits firearm possession by an unlawful user of a controlled substance, the provision’s constitutionality is not suspect. Rather, it is another example of a longstanding prohibition on firearm possession that Heller permits.

If the government proves, as it has charged, that defendant is an unlawful user of a controlled substance and that he was in knowing possession of a firearm, a jury could find defendant guilty of violating 18 U.S.C. § 922(g)(3). Such a conviction would not violate the Second Amendment to the United States Constitution. Nothing in Heller restricts the federal government from criminalizing the possession of firearms by unlawful users of controlled substances.