The American Civil Liberties Union has filed a lawsuit on behalf of a former government prosecutor who was fired after he spoke out against the Obama administration's handling of Guantanamo Bay detainees.

The suit alleges Col. Morris D. Davis was fired from the Congressional Research Service after he wrote an article and letter to the editor critical of Obama's continuation of the military commission trials started by President Bush.

"Col. Davis has a constitutional right to speak about issues of which he has expert knowledge, and the public has a right to hear from him," said Aden Fine, staff attorney with the ACLU First Amendment Working Group, according to a media advisory. "Col. Davis's firsthand experience is invaluable to the ongoing debate over military commissions, and the public should not be denied the chance to hear from him just because he is a public employee."

But he wasn't always a critic. At one point in time, Col. Davis "was the chief prosecutor at Guantánamo Bay and the most colorful champion of the Bush administration’s military commission system," The New York Times noted in 2008.

However, in late 2007, Col. Davis claimed that the Department of Defense had tried to interfere with the prosecutions, seeing "real strategic political value" in convictions.

The final straw was asking Davis to prosecute a detainee with evidence derived from torture. When he spoke out about being ordered to use information obtained through coercion in a prosecution, Davis was released from duty.

"My status as the former chief prosecutor for the military commissions at Guantánamo Bay and my opinions on that subject are completely unrelated to my position at CRS and totally separate from my duties there, and they don't interfere with my ability to do my job," said Davis, according to the ACLU. "The work that CRS does is incredibly valuable and I am proud of the opportunity to continue serving my country after a career in the military. I hope to be reinstated to my original position so I can continue to support Congress at this critical time in our nation's history."

"Government employees do not forfeit their right to comment on matters of public interest," the Times noted in an editorial supporting the colonel's cause. "The Supreme Court ruled in a landmark 1968 case that a public-school teacher had a First Amendment right to write a letter to the editor, as a private citizen, criticizing how his board of education spent money. The employer has interests in the orderly operation of its workplace, the court noted, but they were outweighed by freedom of speech."

The ACLU's lawsuit against the Library of Congress is both an attempt to reinstate Col. Davis to his job and "to reaffirm that governmental employees, including employees of the Library of Congress, may not be terminated for speaking in their private capacities on matters of great public concern," the group said.

The suit "names as defendants James H. Billington, the Librarian of Congress, as well as CRS Director Daniel P. Mulhollan, who is sued in his personal capacity," noted the FAS Project on Government Secrecy.