Old Age Security. Canada (Attorney General) v. Burke
In Canada (Attorney General) v. Burke (Fed CA, 2022) the Federal Court of Appeal considered a situation in judicial review where lower tribunals varied sharply in statutory interpretation in the Old Age Security system (an issue which Vavilov requires to be assessed on a 'reasonableness' SOR at the present court). The issue was whether the Minister of Employment and Social Development could (or could not) retroactively re-assess OAS eligibility when the recipient was not resident in Canada during eligibility periods, that being required by OAS legislation. The court considered the issue extensively [para 55-110], and then concluded that the lower tribunal was unreasonable in their conclusion:
 I agree with the Minister that an interpretation of the powers in section 37 of the Act and section 23 of the Regulations that allows people to keep benefits despite their not meeting the specific residency requirements of the Act is one that is inconsistent with a scheme that provides benefits only to people who meet the eligibility requirement of residency. It is thus unreasonable.. Mudie v. Canada (Attorney General)
In Mudie v. Canada (Attorney General) (Fed CA, 2021) the Federal Court of Appeal considered a judicial review application against a Minister of Employment and Social Development’s (Minister) residency determination for OAS purposes. The case was dismissed on mootness but it is revealing to see how byzantine the OAS eligibility and quantum entitlement process is, both legally and - in this case - practically.
. Pooran v. Canada (Attorney General)
In Pooran v. Canada (Attorney General) (Fed CA, 2021) the Federal Court of Appeal heard a judicial review of an OAS decision of the Appeal Division of the Social Security Tribunal:
 Eligibility for OAS pension benefits is based upon residency. To qualify for an OAS pension, an applicant must establish that they had resided in Canada for 20 years if they are no longer resident in Canada at the time of their application: Old Age Security Act, R.S.C. 1985, c. O-9, subsection 3(2).
 The Old Age Security Regulations, C.R.C., c. 1246, identify certain types of absences that will not interrupt a person’s resident status in Canada. Employment with the Commonwealth Secretariat will not be considered to interrupt a person’s residence status in Canada as long as the applicant returns to Canada within six months of the end of their employment. They must also maintain a permanent place of abode in Canada to which they intend to return, or maintain a self-contained domestic establishment in Canada: subsection 21(5).