Neal Katyal is a professor at Georgetown University Law Center. He’s been a visiting professor at both Harvard Law School and Yale Law School. Last year, the former law clerk to Justice Stephen Breyer was named one of the National Law Journal’s top 40 lawyers under the age of 40. He was co-counsel to Vice President Al Gore during the 2000 election fiasco in Florida. For most people, that’d be enough.

But not for Katyal. He is also the winning counsel in what former acting U.S. Solicitor General Walter Dellinger called “the most important decision on presidential power ever.” Katyal represented Salim Hamdan — Osama bin Laden’s alleged bodyguard/driver. Hamdan was picked up in Afghanistan shortly after September 11, 2001 and sent to Guantanamo Bay, the United States government’s controversial military prison in Cuba. An executive order issued by President Bush provided that Hamdan and other Guantanamo detainees would be tried by military tribunal rather than in a federal court. Hamdan, represented by Katyal, filed a petition for a writ of habeas corpus in a federal district court. Fast forward to June 29, when the Supreme Court concluded that the executive branch lacked the authority to set up such tribunals, which it also deemed violative of the Geneva Conventions and the Uniform Code for Military Justice.

Katyal graciously talked with me by email about the case, Gitmo, fan mail, and what he drinks to celebrate a Supreme Court victory.