 There is no credible information available on illegal immigration in Canada.Estimates range between 35,000 and 120,000 illegal immigrants in Canada.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.