There is no credible information available on illegal immigration in Canada.
Estimates of illegal immigrants range between 35,000 and 120,000 and according to some estimates go even higher, up to 100,000 and 200,000 people.
James Bissett, a former head of the Canadian Immigration Service, has suggested that the lack of any credible refugee screening process, combined with a high likelihood of ignoring any deportation orders, has resulted in tens of thousands of outstanding warrants for the arrest of rejected refugee claimants, with little attempt at enforcement.
A 2008 report by the Auditor General Sheila Fraser stated that Canada has lost track of as many as 41,000 illegal immigrants. This number is predicted to increase drastically with the expiration of temporary employer work permits issued in 2007 and 2008, which were not renewed in many cases because of the shortage of work due to the recession.