The Supreme Court’s 6-3 conservative majority and repeated signals from Justices Kavanaugh, Thomas, Alito, and Gorsuch that AR-15-style rifles qualify as “arms in common use” under Heller and Bruen form the core driver behind traders’ 86.5% odds that the Court will invalidate state and local assault-weapons bans. In late June 2026 the justices granted certiorari and consolidated challenges to Cook County, Illinois, and Connecticut prohibitions, setting oral arguments for the fall term with a decision expected by mid-2027. Lower courts had upheld the measures, but the Court’s recent expansion of Second Amendment protections and the rifles’ widespread lawful ownership make reversal the consensus view. Oral argument performance or an unexpected vote from Chief Justice Roberts or Justice Barrett remain the main variables that could shift probabilities.