The number of Canadians who have lost their citizenship through obscure sections of the 1947 Citizenship Act is far greater than the federal government has admitted, CBC News has learned.

The issue gained attention at the beginning of this year when thousands of people applied to get passports after the U.S. toughened entry rules — only to discover they were not considered Canadians.

While Citizenship and Immigration Minister Diane Finley says her department is only dealing with 450 cases of so-called "lost Canadians," new documents obtained late last week by CBC News show that her department has stripped citizenship from nearly 4,000 Canadians in just seven years.

They include the wives and children of Canadian soldiers who were born abroad, anyone born abroad whose parents failed to sign a Registration of Birth Abroad form, people considered to have been born out of wedlock to a non-Canadian mother and people who fall into several other categories.

CBC applied under the Access to Information Act for computerized records from the Citizenship and Immigration (CIC) Department's case-processing centre in Sydney, N.S. Those records show the number of people who have had their citizenship denied or taken away under five sections of the 1947 Citizenship Act.

In total, there were 3,962 cases of people who lost their citizenship between 1998 and 2004, an average of 566 people a year.

CIC says it does not have records for 2005 and 2006, or prior to the introduction of their computerized system before 1998. However, the same laws have been used to take citizenship away from Canadians for 60 years, indicating that tens of thousands of people may have been affected during that time.

Thousands could be at risk

In addition, it's believed there are thousands more people who are at risk of losing citizenship, but who have not yet been identified by Citizenship and Immigration Canada. Currently, for the year 2006-07, CIC is dealing with an additional 450 cases, bringing the number of known Lost Canadians in the past decade to well over 4,000.

The data appears to contradict what Finley has previously said. Earlier this year, she told the Commons citizenship and immigration committee that her department only knows of a small number of cases.

"While the problem is real and deserves immediate attention," she said at a committee hearing Feb. 19, "there's no evidence it’s as massive as has been reported in the media, or has been portrayed by some honourable members."

During question period Monday, Finley maintained the 450 number when criticized by Liberal MP Andrew Telegdi that she was "downplaying the issue," adding her department, which established a special hotline with dedicated agents, has already restored citizenship to 33 of those people.

But demographics expert Barry Edmonston of the University of Victoria said the recent findings correspond to the research he's already done for CBC on the issue of Lost Canadians.

Data studied

Edmonston studied census and immigration data to estimate how many people are at risk of losing their citizenship under sections of the 1947 Citizenship Act.

"If you add up the six different groups, it's somewhere in the range of 100,000 to 200,000 people affected by the 1947 Citizenship Act," he said.

Many of those people may have dealt with their citizenship issues already, Edmonston said, adding he believes the majority are still at risk if they try to apply for passports or Old Age Security.

"Thousands and thousands, if they were to have their citizenship reviewed, would have potential problems, and that's the number I'm trying to deal with."

When the hearings into the issue resumed in Ottawa on Monday, Finley said she was open to making changes to the Citizenship Act if that's what the committee recommends.

Edmonston was the star witness on Monday, and the citizenship and immigration committee was also expected to hear from several highly placed staff members within the department.