Canadian journalists have no constitutional protection to keep the identity of their sources secret, the Supreme Court of Canada ruled Friday.

The court ruled 8-1 against the National Post and reporter Andrew McIntosh, who were seeking to quash a 2001 search warrant issued in the Shawinigate affair.

The justices upheld the legality of the warrant which demanded that the Post and McIntosh hand over a brown envelope and a document supplied by a confidential source.

The newspaper argued that turning over the material for DNA and fingerprint tests would likely reveal the identity of the source, known in court documents as "Person X."

But the court says journalists have no broad constitutional immunity to protect sources and any such claims have to be weighed on a case-by-case basis.

Justice Ian Binnie wrote in the court's decision that in the Post case, the needs of a police investigation override any public interest in confidentiality of a journalist's sources.

"The law should and does accept that in some situations the public interest in protecting the secret source from disclosure outweighs other competing public interests -- including criminal investigations," Justice Ian Binnie wrote on the court's behalf.

"In those circumstances, the courts will recognize an immunity against disclosure of sources to whom confidentiality has been promised."

Lawyer Peter Jacobsen, who intervened in the case on behalf of the Globe and Mail, said the court did not break new ground in Friday's ruling.

The Supreme Court of Canada went out of its way to emphasize the importance of confidential sources to journalists … but said it is not an absolute right," he told CTV News Channel.

"I don't think this makes a huge change in the law."

McIntosh, who now works as a reporter for the Sacramento Bee in Sacramento, Calif., had been investigating links between then-prime minister Jean Chretien and the Grand-Mere Inn, a resort in his home riding, in 2001.

McIntosh reported that Chretien had called the Business Development Bank of Canada to promote a loan for the inn.

He subsequently received an envelope from X containing what appeared to be a 1997 internal loan document from the bank. It said a $615,000 loan to Grand-Mere allowed the company to pay an outstanding $23,000 debt to a Chretien family corporation.

The bank said the document was a forgery. McIntosh testified that X told him the document had arrived by mail anonymously and X forwarded it, believing it to be genuine.

In 2001, the RCMP were called in and asked to test the document and envelope for DNA or fingerprints -- which would likely have identified X.

They obtained a search warrant and an assistance order requiring the National Post to help find the document, which McIntosh said he had hidden.

The newspaper went to court to fight the warrant and order, winning in Ontario Superior Court but losing in the provincial court of appeal.

The Supreme Court heard the case last May.