The report by Auditor General Sheila Fraser criticized the Canada Border Services Agency for failing to monitor observance of its removal decisions. The agency said in the report that it agreed with all of the auditor's recommendations for improvements.
Fraser's report said the agency lacked contact information for 41,000 of the 63,000 people ordered to leave the country as of September 2007. It said the majority ordered deported were rejected refugee applicants and didn't pose "a very high risk to the public."
The report said the agency removed about 12,600 individuals in 2006 and 2007, including 1,900 criminals who "posed a high risk to Canada."
The border agency has the power to detain foreign nationals and permanent residents who are considered a risk or danger to the public and to deport people ruled ineligible to enter Canada.
Canada has long prided itself for opening its doors to immigrants and asylum-seekers but critics have long complained that the United States' northern neighbor is too lax on illegal immigration.
Parliament member Ujjal Dosanjh of the opposition Liberal party criticized the government for not doing more. "How do we know that all 41,000 are harmless? We don't know," Dosanjh said.
The report said the precise number of people remaining illegally was impossible to determine due in part to the fact that the government does not record departures from Canada.
Some of the monitoring problems were traced to an aborted plan to replace a computerized case management system, originally intended to be in place three years ago.
Public Safety Minister Stockwell Day said the government was acting on Fraser's advice.
"The CBSA has already put in place quite a few of the recommendations that she has talked about, so we're improving. It's not perfect yet but it's a big improvement over what it has been," Day said.
