In her decision, Superior Court Justice Mary Vallee said her sealing order of last December must stand and none of the information can be released.
"All of the information in those materials and the (sealing) order relates to a subject matter which must be protected from disclosure," her ruling states.
"Because the subject matter must be protected, I am not at liberty to describe the nature of the subject matter or why it must be protected."
The unusual circumstances arose in December during a civil suit involving allegations of harassment within the RCMP filed by Sgt. Peter Merrifield, who alleges senior officers ruined his career after he launched an unsuccessful bid to run for the federal Conservatives in 2005.
In December, Merrifield called "Witness X" to testify but the proceedings went in-camera and Vallee ordered material related to the hearing sealed, including a copy of her sealing order itself.
The National Post, citing sources, has reported the material at issue includes four letters sent by private investigator Derrick Snowdy to assistant RCMP commissioner Stephen White, and the letters contain allegations the RCMP leaked private information about Harper's family.
The federal government maintains that Section 37 of the Canada Evidence Act — sometimes used in terrorist cases — allows for confidentiality where openness would encroach on the public interest.
At a hearing earlier this month, Brian MacLeod Rogers, a lawyer for a media consortium, pressed the principle of open-court proceedings.
While protecting the identity of a confidential informant posed no problem, Rogers argued, the government had to do more than make general claims the public interest would be harmed by releasing information in a case involving allegations of wrongdoing by the country's national police force.
Vallee agreed the public should only be shut out of court proceedings in "extraordinary circumstances," but rejected the call to lift the veil as much as possible.
"Disclosure of redacted versions of the materials and the (sealing) order would be meaningless because all of the text in the materials and the order would have to be redacted," she said Thursday.
Rogers, who spoke for Postmedia News, CBC, Maclean's and the Toronto Star, was not immediately available to comment on the ruling. Merrifield's lawyer, Laura Young, who has said her client wants his case to be heard and "understood publicly," had no comment.
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