Both the federal government and suspected terrorist Mohamed Harkat can claim partial victories, after the Federal Court of Appeal issued a complex ruling Wednesday on the process that placed Harkat under a security certificate.

In its ruling, the court upheld the constitutionality of the government's security certificate process.

However, it referred Harkat's case for a new hearing because the Ottawa man was not privy to the full contents of recorded evidence used against him. Those recordings have since been destroyed in keeping with policy of the Canadian Security Intelligence Service.

The court said the summaries of this evidence may not be submitted as evidence at the new hearing.

The court also ruled that it was wrong for Harkat's trial judge to create a special "class privilege" for CSIS informers that guaranteed them rights to confidentiality and anonymity similar to police informants.

Harkat's lawyers said Wednesday the fact the ruling calls for some evidence to be excluded at the new hearing will work in their client's favour.

"We believe this will have a profound effect for the good of our client," Matt Webber said.

Lawyer Norm Boxall said he is happy for Harkat but "we remain solidly of the belief this (security certificate) regime is unconstitutional."

Public Safety Minister Vic Toews said he is pleased the court upheld the constitutionality of the security certificate process, calling it "an important tool in an array of tools."

The Ottawa gas station attendant and pizza delivery man was arrested in December 2002 on accusations that he had affiliations with al Qaeda, allegations he denies.

Harkat was released from custody under strict conditions that include a ban on using a cellphone or a computer, and he continues to wear a GPS bracelet.

His lawyers have also been fighting a deportation order to Harkat's native Algeria.

Harkat told reporters Wednesday that while his legal battle is not over, the ruling "gives me another day to breathe on this earth."

"It's not over but at least one day I'm going to see the light at the end of the tunnel," he said.

In February 2007, the Supreme Court of Canada ruled that the security certificate process was unconstitutional. The federal government revised the law in 2008 to include a "special advocate" provision, which allows lawyers who are given special security clearance to hear the government's evidence and ensure the accused's rights are protected.

Harkat's lawyers have argued that despite the presence of these special advocates, suspects are still not privy to all the evidence against them. But on Wednesday, the court ruled that the use of these special advocates is constitutional.

With files from The Canadian Press