The hand-held scanner (a PD-4 sniffer) that Air India was using to scan luggage and passengers in 1985 -- when there were several threats being issued by extremists -- was 'useless', says a former Royal Canadian Mounted Police officer.

Gary Carlson, an RCMP bomb expert, told Justice John Major on Tuesday in Ottawa that the device that was being used by Air India as a back-up to x-raying bags on its weekly flight to India that stopped in Toronto and then Montreal, was ineffective unless it was an inch away from open explosives.

According to his testimony, Garlson said, six months before the tragedy, "I had a vial of gunpowder that I brought to this test. I placed it at the bottom of a garbage can and put the lid back on. There was no reaction from the machine (scanner)."

There was, then, a discussion amongst the RCMP officers that 'this machine wasn't detecting anything'.

Carlson was so concerned about that ineffective machine that he stressed to the Air India official to call him any time there was a suspicious bag or parcel. He had with him a bomb expert sniffer dog, Thor.

"In all the time Air India came into Toronto, I did not receive a single call," he said.

His testimony comes in the wake of last week's testimony of Serge Carignan, who was a police officer in Montreal and on call with his dog Arko on that fateful night. 

Carignan said last week he was called by an RCMP officer at about 9.30 pm on the night of June 22 to rush to the airport to check a 747 Boeing and the luggage. By the time he reached the airport at about 10.15 pm, the plane had already taken off. 

Therefore, when the X-ray machine reportedly broke down at the Pearson airport in Toronto on June 22, with 60 suitcases were still to be checked, Air India staff, Carlson said, used the same hand-held device that had been proven useless a few months before.

The suitcase with the bomb that came on another flight from Vancouver and was amongst the final bags screened and loaded on to Flight 182.

It is now clear that the bags were not properly screened either in Toronto or in Montreal, leading to the death of 329 people.

Hearings in the Kanishka case will continue through the week.