Last month, I interviewed Robert Levy, the Cato Institute senior fellow and constitutional lawyer, who successfully used a broad interpretation of the Second Amendment to overturn the D.C. gun ban in March. When the D.C. Circuit Court of Appeals ruled in favor of Levy's case, Parker v. District of Columbia, it dissolved the strictest gun regulations on the books in any state and marked the first time this interpretation of the Second Amendment has been used to successfully overturn a state's gun law. When Levy and I spoke about his victory, he mentioned the likelihood that Parker would go before the Supreme Court. Today, that likelihood just got greater. The D.C. federal appeals court denied D.C.'s request for a second ruling before the entire court. (Originally, the case was heard before a three-judge panel.) So, Levy is likely off to the Supreme Court. Gun laws beware! If Parker is upheld in the Supreme Court, the ruling will jeopardize state gun laws across the nation, making them vulnerable to more legal challenges.