Garre returned to government in September 2005 as Principal Deputy Solicitor General. In this role, he represented the government in "Munaf v. Geren", 553 U.S. 674 (2008), arguing before the Supreme Court that U.S. federal courts lacked jurisdiction over two U.S. citizens being held by the military in Iraq based on "Hirota v. MacArthur", a 1948 Supreme Court case that "rejected habeas corpus petitions from Japanese prisoners who had been convicted of war crimes by an international tribunal". He also won "Baze v. Rees" (2008).