The only US army officer to be charged over the Iraq jail abuse scandal has been cleared of any wrongdoing by the US military authorities.
Lt-Col Jordan was the highest-ranking soldier to have been charged
Lt-Col Steven Jordan was in charge of the Abu Ghraib prison's interrogation unit when pictures of US soldiers abusing prisoners were taken in 2003.
He was cleared of mistreatment charges in August, but convicted of disobeying orders not to discuss the inquiry.
That conviction has now been thrown out, angering human rights campaigners.
They say the US military failed to investigate those further up the chain of command over the Abu Ghraib scandal, despite promising to do so.
Eleven lower-ranking soldiers have been convicted of carrying out abuses at Abu Ghraib - with sentences ranging from a few hours of community service to up to 10 years in prison.
Lt-Col Jordan did not appear in any of the photographs, which showed naked Iraqi prisoners forced to lie on top of each other and others with dog leads around their necks.
He had pleaded not guilty to all charges at his court martial but acknowledged emailing a number of soldiers about the investigation, contrary to orders not to discuss the case.
His defence had argued that although he was nominally in charge of the interrogation centre, Lt-Col Jordan did not have direct control over the interrogations.
Major General Richard J Rowe, commander of the Military District of Washington, threw out the conviction this week and ordered that Lt-Col Jordan receive an administrative reprimand, which leaves no written judicial record of the case.
But human rights advocates said the decision sent a troubling message.
"It could not be more clear that prisoner abuse in Iraq and Afghanistan resulted from policies and practices authorised by high-level officials, including military and civilian leaders," said Hira Shamsi, of the National Security Project of the American Civil Liberties Union.
"Although the abuse was systemic and widespread, the accountability for it has been anything but."
Lt-Col Jordan told the Associated Press he agreed that there were enlisted soldiers and officers responsible for the abuse at the prison who escaped prosecution.
But he said he felt victimised by press coverage that was eager for an officer to be blamed.
"Everybody that's seen all the evidence and looked at it, or the lack of it, realises that Steve Jordan had nothing to do with abusing detainees at Abu Ghraib," he said