Transportation experts and privacy advocates warned of potential abuses as Canada's no-fly list, which checks the names of domestic airline passengers against a list of people deemed to be threats, went into effect on Monday.

Fewer than 1,000 names are believed to be on Transport Canada's Specified Persons list, unlike its U.S. counterpart, which has grown to contain more than 44,000. The list will not be available to the public, which means those on it will only find out when they try to travel.

The "dynamic" list will be adjusted as intelligence agencies such as CSIS and the RCMP evaluate "reliable and vetted" information, said Allan Kagedan, chief of aviation security policy for Transport Canada.

"The numbers will change, so I'm not sure what there's a real point in identifying a number," Kagedan told CBC News on Monday.

Barry Prentice, director of the Transport Institute at the University of Manitoba in Winnipeg, said the list is "sort of a charade" to make people feel like they have greater security.

"I don't think it's going to help one bit," Prentice told CBC News. "What terrorist is going to travel with their own name and passport? These people are going to steal or create a forged passport and identification if they're going to do anything, anyway."

Furthermore, Prentice warned, some travellers could be wrongly identified as security risks under the Passenger Protect program — and wind up with all kinds of problems.

'It is difficult to know where the balance lies'

But Kagedan said such lists have proved invaluable to making air travel safer, and Canada's version balances security needs with privacy concerns. 

"They do work," he said. "The problem with giving examples is that they defeat security and also, ironically, defeat the privacy rights to those individuals."

Lindsay Scotton, who does impact studies for Canada's privacy commissioner, agreed aviation security is important. But she expressed concern that denying an individual the right to fly based on suspicion erodes the cherished concept that a person is innocent until proven guilty.

"In a security-conscious world, it is difficult to know where the balance lies," she told CBC News. "It can have very serious and profound ramifications if somebody is on a list that is used for purposes that interfere with their civil liberties."

Scotton also said Transport Canada has failed to prove that no-fly lists work.

"To date they haven't supplied us with any information that shows the list meets that need," she said.

MPs critical

During Monday's question period, Liberal MP Joseph Volpe demanded the government disclose the identities of those on the no-fly list.

NDP MP Joe Comartin suggested if the government won't scrap the list that it at least set up an ombudsman to handle cases where innocent people are placed on the list.

Transportation Minister Lawrence Cannon didn't provide names, but he said the government adheres to guidelines that determine who makes the list and that there is recourse for innocent people.

Arar case cited

Critics also point to the ordeal of Canadian Maher Arar, who was sent by U.S. officials to Syria, where he was detained and tortured for more than a year. Despite being exonerated by federal inquiry in Canada, Arar remains on a U.S. watch list.

Muslims are already subjected to increased scrutiny at airports and the no-fly list could add to that, said former Alberta MLA Larry Shaben, now president of the Edmonton Council of Muslim Communities.

"I think it's just an excessive layer of bureaucratic interference," Shaben told CBC News. "Among Muslims, there's a great similarity in names and it's very easy for names to be the same or similar."

Who may be placed on the no-fly list:
An individual who has been involved in a terrorist group and who, it can reasonably be suspected, will endanger the security of any aircraft or aerodrome, or the safety of the public, passengers or crew members. An individual who has been convicted of one or more serious and life-threatening crimes against aviation security. An individual who has been convicted of one or more serious and life-threatening offences and who may attack or harm an air carrier, passengers or crew members.
Source: Transport Canada

In May, the federal government announced that as another part of the Passenger Protect program, all travellers 12 and older on flights within Canada, from Canada and destined for Canada would have to show valid photo identification or two pieces of additional ID, one of which shows date of birth, name and gender, before they will be issued a boarding pass.

In June, the government said it was temporarily easing the rules so that travellers in Canada who appear to be between 12 and 17 years of age would require only one piece of government-issued identification, with or without photo, before boarding an aircraft.

The exemption for travellers under 18 in Canada will be in place until Sept. 18, officials said.