A Montreal man accused of having links to terrorists won a victory on Thursday, with a Supreme Court ruling that CSIS was wrong to destroy evidence against him.

Adil Charkaoui's right to a fair trial was violated by the spy agency's decision to destroy two interviews with Charkaoui from 2002, said CTV's Rosemary Thompson, reporting from outside the court.

Content from the interviews was used by CSIS to obtain a security certificate that would allow Charkaoui's deportation.

In one of the interviews, he purportedly talked about strategies for recruiting others to the terrorist cause. But CSIS, in what the agency said is standard practice, destroyed the tapes and kept only summaries of what was said.

On CTV Newsnet, Charkaoui said that CSIS needs to change the way it operates.

"We are not talking about two interviews, it's the whole politics of CSIS," he said. "It's against the charter and against the law."

Thompson told CTV Newsnet that the Supreme Court agreed with Charkaoui's argument.

"When the security certificate was going to the courts, obviously (Charkaoui) wanted to get the notes or the interview tapes to see the real evidence rather than the summary. But it turned out CSIS had destroyed the notes, so the Supreme Court is saying that's a problem," Thompson said.

"You can't from a summary know exactly what was in the notes, the actual words, what was said, the back-and-forth between the agents and Mr. Charkaoui. And they said the destruction of evidence is something that has to be changed."

The ruling is a moral victory for Charkaoui, a school teacher and part-time graduate student in Montreal who has been fighting deportation on a security certificate to his native Morocco.

The court said it wasn't going to quash the security certificate against Charkaoui and he would have to continue his fight.

Charkaoui said that CSIS has "nothing" on him except the interviews and was confident that he would be found innocent in an open trial.

"I am asking them to make my case public," he said. "CSIS cannot use the national security argument to violate human rights in Canada."

Michel Juneau-Katsuya, a former CSIS agent, told CTV Newsnet that he expects the ruling will "force CSIS to change the way they operate."

He said the CSIS policy went back to 1994, stating that after an officer was finished with their notes, they needed to destroy them.

He said that policy was in part because the organization did not want its agents to have to testify in court with their notes, like a police officer does.

"The logic is, you don't need your notes, because after you translate everything into your report, the report basically becomes your notes," Juneau-Katsuya said.

At a news conference on Thursday, Charkaoui said he considered the ruling a full victory despite the fact the proceedings against him will continue.

"For the first time these people are brought back into line. They can't destroy proof and put into files national security summaries without any context," Charkaoui said.

"I'm very satisfied with the decision and I hope this will have an impact, not only on immigrants but on every citizen."

His next appearance before the federal court is scheduled for October.