While the case was pending in his court, Roberts was interviewing with high White House officials — including Atty. Gen. Alberto R. Gonzales, Vice President Dick Cheney and Deputy Chief of Staff Karl Rove — for a seat on the Supreme Court. In the words of the federal law on judicial disqualification, this placed the judge in a situation where "his impartiality might reasonably be questioned."
Instead, Roberts cast a swing vote ruling that the Geneva Convention doesn't apply to accused Al Qaeda members.
Harvey Silverglate wrote a prescient criticism of the Supes' expansions of Executive authority in January 2005.