"When we used the term ‘specific,’ it meant that we had something that we could pass on and (police) could act upon it," John Henry testified Tuesday at a public inquiry.

"However, in most cases we had nothing specific."

The terminology is important because, for more than two decades, the federal government has insisted that police and security forces had no advance intelligence indicating a specific threat to Air India Flight 182.

Former diplomat James Bartleman sparked a storm last week when he contradicted that mantra, insisting he had seen an electronic intercept just days before the bombing suggesting Air India would be targeted by Sikh extremists on the coming weekend.

Most of the ensuing controversy has centred on whether Bartleman’s memory is accurate. But a related question is how intelligence analysts perceived the multitude of other warning signs that preceded the bombing.

Henry, who was head of threat assessment for the Canadian Security Intelligence Service, wasn’t questioned directly about the incident described by Bartleman. But he painted a broader picture of a system in which any tip had to clear a high hurdle to prompt an immediate response.

That calls the whole approach to intelligence analysis into question, said Norm Boxall, one of the lawyers for the families of the Air India victims.

The threshold for defining something as a specific threat is so high that it "almost means being certain that a crime is in progress at a given moment," Boxall said outside the hearing room.

The problem was illustrated by a warning in April 1985, apparently from Indian government sources, that an Air India plane headed for Canada could be hijacked before reaching its destination.

Asked if that would qualify as a specific threat, Henry replied: "It’s leading in that direction (but) we would want corroboration of some kind before we became definitive about saying this is a definite threat."

In another celebrated case, Air India sent a warning to the RCMP in early June 1985 — three weeks before Flight 182 went down — saying its planes could come under attack through either timebombs or suicide squads.

The Mounties failed to pass that warning on to CSIS, and the spy service continued to list Air India as facing only a "general" threat of attack. But Henry said that, even if his analysts had seen the missing information, they may not have changed heir minds.