An Ontario court has struck down sections of Canada's secrecy law in throwing out RCMP warrants used to search a reporter's home.

The Ontario Superior Court judgment released Thursday quashes three sections of the so-called leakage provisions of the Security of Information Act, passed following the 9/11 terrorist attacks on the United States.

A story written by reporter Juliet O'Neill, shown in a file photo, prompted a police search that was at the heart of Thursday's Ontario Superior Court ruling.
(CBC)

The provisions were directly drawn from the decades-old Official Secrets Act, long criticized as archaic and poorly drafted.

David Paciocco, a lawyer for Ottawa Citizen reporter Juliet O'Neill, says the ruling underscores the media's role in protecting democracy.

"It's a tremendous affirmation of the importance of freedom of the press and freedom of expression," Paciocco said after reading the judgment.

"This is also an ultimate vindication of Ms. O'Neill."

Squads of Mounties combed through O'Neill's home and office on a cold January morning in 2004 in an attempt to find the source of information about the Maher Arar affair.

Arar, a Canadian-Syrian telecommunications engineer who had been living in Ottawa, was detained at a New York airport in 2002.

He spent months behind bars in Damascus after being deported to his Syrian birthplace by U.S. authorities.

Article by reporter sparked search

The RCMP launched a criminal probe in the weeks following publication of a Nov. 8, 2003, story by O'Neill.

The story cited a "security source" and a leaked document offering details of what Arar allegedly told his Syrian captors.

The Mounties said they believed O'Neill published her article "based on the receipt of secret classified information."

O'Neill's legal team argued the Security of Information Act provisions used to obtain the RCMP search warrants violated the Charter of Rights and Freedoms.

They said the anti-leakage sections were vague, too far-reaching and at odds with the constitutional guarantee of a free press.

Paciocco said the court ruling by Justice Lynn Ratushny effectively renders the warrants null and void.

If not appealed to the Supreme Court of Canada, the decision would pave the way for the return of O'Neill's seized papers, notebooks, contact listings and computer files.