you can ask a candidate, on an application or in an interview, if she is legally entitled to work in Canada. However, you cannot ask if she is a Canadian citizen, a permanent resident, has a work permit or ask to see her social insurance number. You also can’t ask about place of birth, refugee status or religion.
Once you have made a conditional offer of employment, then you can ask for proof of eligibility to work in Canada, such as a social insurance number or a work permit. This is also when you can ask for copies of diplomas, degrees, certificates or professional credentials.