The binding legal principles established are: (1) Section 38(d) public interest standing requires showing that the applicant is genuinely acting in the public interest, considering factors such as: whether there are other reasonable and effective means to bring the challenge; the nature and general application of relief sought; vulnerability of affected persons; nature of the rights implicated; and consequences of infringement; (2) The Bill of Rights, particularly sections 12 and 35(2), applies to all persons physically within South African territory, including foreign nationals at ports of entry who have not been formally admitted; (3) Section 34(8) of the Immigration Act must be interpreted as requiring immigration officers to have reasonable grounds to suspect a person is an illegal foreigner before detention is triggered - it does not permit detention based on mere assertion; (4) Immigration detention without court oversight beyond 30 days (extendable to 90 days) is not justified under section 36 and violates section 12 of the Constitution; (5) Where a statute can reasonably be interpreted in a manner that preserves constitutionality without unduly straining language, courts must adopt that interpretation; (6) Where a provision is unconstitutional only to a limited extent, courts should prefer reading in the missing protection to striking down the entire provision.