Among the pro bono lawsuits that lawyers for Guantánamo Bay detainees have filed over the years, William Livingston’s win last year for a Yemeni man marked a rare accomplishment.

The Covington & Burling senior counsel has been leading a team that has filed habeas corpus petitions challenging the imprisonment of seven Yemeni men held for more than a decade without charges at the naval base. Covington began filing the suits in 2004, but they didn’t gain traction until the U.S. Supreme Court in 2008 upheld the detainees’ right to petition for writs of habeas corpus.

A district court order made one of Livingston’s clients, Mohamed Mohamed Hassan Odaini, the first of the seven men to get sent back. His release came despite a moratorium the Obama administration placed on the release of detainees to Yemen after someone with ties to an al-Queda-affiliated group from that country tried to blow up a plane in December 2009.

“As far as I know, he was the last detainee sent to Yemen,” Livingston said. Odaini’s case was the only one of five habeas petitions Covington won that did not result in an appeal by the government. U.S. District Judge Henry Kennedy granted Odaini’s habeas writ in May 2010, writing in a 36-page opinion that the evidence presented by the government “shows that holding [the defendant] in custody at such great cost to him has done nothing to make the United States more secure.” — Nate Raymond