O'Connor, who was appointed commissioner of the probe last week, will look into the detention of Arar in the United States, his deportation to Syria via Jordan, his imprisonment in Syria and his return to Canada.

The terms also call on the commissioner to investigate "any other circumstance directly related to Mr. Arar that Justice O'Connor considers relevant to fulfilling this mandate."

It wasn't immediately clear if that means O'Connor - an Ontario appeal court judge who headed the inquiry into the tainted-water tragedy in Walkerton - will be able to investigate a controversial leak of information about Arar by anonymous security officials.

O'Connor has also been asked to make recommendations concerning an independent, arm's-length review mechanism for the RCMP's activities with respect to national security.

"Under the policy review of possible review mechanisms for RCMP national security activities, Mr. Justice O'Connor will examine domestic and international review models," said a government statement.

"He will make such recommendations as he considers advisable on the creation of a new mechanism and in doing this, he will consider how the recommended mechanism would interact with other Canadian review bodies."

There are currently two other inquiries under way - one by the Security Intelligence Review Committee, which monitors the country's intelligence service, and another by the Commission for Public Complaints Against the RCMP.

Deputy Prime Minister Anne McLellan has said O'Connor will build on those two inquiries, adding as many of his findings as possible will be made public.

Arar, a 33-year-old husband and father, has consistently called for a public probe since he was returned to Canada in the fall.

The engineer and Syrian-born Canadian citizen was detained Sept. 26, 2002, as he passed through JFK International Airport in New York on his way home from a vacation in Tunisia.

The dual citizenship was deported Oct. 8, flown to Jordan and driven in a car from there to Syria, where he spent a year of solitary confinement in a small cell.

He said he endured the confinement and torture until October, when he was released without explanation.

Arar has maintained his innocence, though he acknowledged he falsely confessed to attending an al-Qaida training camp to curtail his torture.

He filed a lawsuit against U.S. Attorney General John Ashcroft and other top U.S. officials last week alleging they knew he would be tortured when they deported him to Syria in 2002.

Arar had also been pondering a suit against the Canadian government. His lawyers have filed a multimillion-dollar lawsuits against Syria and Jordan, where he was first sent from the United States.

Canadian officials have said American authorities made a mistake in deporting him.

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