The Conservative government has refused a parliamentary committee's request to allow the military's former top lawyer to testify without legal restrictions on the Afghan detainee affair, CBC news has learned.

Ken Watkin, Canada's former chief military prosecutor, said his involvement with the Afghan detainee file was covered by solicitor-client privilege. (Dan Balilty/Associated Press)Letters obtained by CBC news show that Defence Minister Peter MacKay was unwilling to waive the government's right to solicitor-client privilege when it comes to the testimony of the military's one-time senior legal adviser, despite a request for it to do so from the House of Commons special committee on Afghanistan.

Last November, retired brigadier-general Ken Watkin, a former judge advocate general of the Canadian Forces, was called to testify before the committee as it investigated the Canadian government's handling of Afghan detainees.

During his committee appearance, Watkin refused to answer several questions on what he knew about the government's detainee policies, sparking a series of heated debates with MPs.

Watkin claimed he couldn't say whether he'd seen certain detainee reports from the Department of Foreign Affairs. At another point in his testimony, he refused to say whether he had read articles in the Globe and Mail that alleged torture and abuse of detainees.

"My involvement in this file has been as a legal adviser to the government of Canada, and that involvement is covered by solicitor-client privilege," Watkin said in response to Liberal committee member Ujjal Dosanjh's questions.

Watkin's refusal to answer prompted questions and condemnation from Opposition MPs, who were trying to find what the government knew about the alleged torture of Afghan detainees, and when it knew it.

"I'm not sure whether it helps to be a lawyer or a fisherman at the moment," quipped Liberal MP Bryon Wilfert.

Military documents obtained under the Access to Information Act by the CBC's investigative unit show the defence minister refused the committee's request to waive solicitor-client privilege to allow Watkin to speak more freely.

Conservative MP Rick Casson, the committee's chair, made the request at the end of November.

"As you are aware, solicitor-client privilege belongs to the client and not to the lawyer," Casson wrote. "The Committee has requested that the Government of Canada waive its privilege in order to allow Brigadier General Watkin to answer questions."

MacKay's response was sent on Dec. 9, 2009, the same day he and former defence minister Gordon O'Connor appeared before the committee and faced an acrimonious grilling.

In the response, MacKay quoted case law supporting a client's right to confidentiality in its dealings with its lawyer, and then simply refused the committee's request.

"The privilege belongs to the government as a whole," he wrote, "and it will not be waived."