As of today the ACLU and Human Rights First are suing Rumsfeld and others on behalf of eight former detainees, charging the eight were tortured as a direct result of Rumsfeld's actions. The lawyers for the plaintiffs plan to pursue monetary damages under the auspices of the Alien Tort Claims Act. Here's Reuters:

The American Civil Liberties Union and Human Rights First filed suit in federal district court in Rumsfeld's home state of Illinois on behalf of eight former detainees who said they were severely tortured. All eight were subsequently released without being charged.

"Secretary Rumsfeld bears direct and ultimate responsibility for this descent into horror by personally authorizing unlawful interrogation techniques and by abdicating his legal duty to stop torture," said Lucas Guttentag, lead counsel in the case. [ ... ]

The ACLU filed similar complaints against three other senior officers: Col. Thomas Pappas, Gen. Janis Karpinski and Lt. Gen. Ricardo Sanchez on behalf of prisoners mistreated at Iraq's Abu Ghraib prison.

The suit against Rumsfeld focuses on an order he signed on Dec. 2, 2002 that authorized new interrogation techniques for detainees in the "war on terror" being held at Guantanamo Bay in Cuba. These included "stress positions," hooding, 20-hour interrogations, removal of clothing, exploiting phobias, prolonged isolation and sensory deprivation.

When evidence became overwhelming that prisoners were being tortured, Rumsfeld turned a blind eye, the suit alleges.

Here is the full text of the complaint against Rumsfeld as a PDF (beware it's 77 pages long), and here is information regarding the eight plaintiffs and their allegations. I recommend reading through that last link to get a sense of what we are talking about here. I follow these matters pretty closely and was surprised that some of the specific charges were new to me.

The Department of Defense issued a terse statement regarding the case:

There are 4 civil complaints under review within this Department and at the Justice Department.

We vigorously dispute any assertion or implication that the Department of Defense approved of, sanctioned, or condoned as a matter of policy detainee abuse.

No policies or procedures approved by the Secretary of Defense were intended as, or could conceivably have been interpreted as, a policy of abuse, or as condoning abuse.

There have been multiple investigations into the various aspects of detainee abuse.

None has concluded that there was a policy of abuse.

The Department of Defense has demonstrated a record that credible allegations of illegal conduct by U.S. military personnel are taken seriously and investigated.

- There have been 8 major reviews, inspections, and investigations; three more are in progress.

- To date, more than 100 individuals have undergone, or are undergoing, disciplinary proceedings. We anticipate there may be additional proceedings against additional individuals.

U.S. policy as expressed in relevant Defense Department orders, techniques, and procedures requires that detainees be treated humanely and in accordance with the law.

- The Geneva Conventions apply to the conflict in Iraq.

- The Al Qaeda and Taliban are unlawful enemy combatants who fail to comply with the laws of war.

- The President has ordered and Defense Department policy emphasizes that Al Qaeda and Taliban detainees be treated humanely and, to the extent appropriate and consistent with military necessity, in a manner consistent with the principles of Geneva.

The above says little but says enough to constitute an admission of guilt. The Department of Defense says that it seeks to treat detainees in "a manner consistent with the principles of Geneva" to "the extent appropriate", but as a body of ratified treaties the Geneva conventions have become part of US law and, further, The War Crimes Act of 1996 explicitly defines "grave breach" of the Geneva conventions as a war crime. It is just as illegal for Rumsfeld to qualify the extent to which those under his command should follow Geneva as it would be for him to personally honor statutes forbidding theft or murder only to the extent that he deems appropriate.