Mental incapacity as a jurisdictional objection needs evidence, not just an assertion

A petitioner alleged an unauthorised letter had been written about him in breach of Articles 10 and 31. The respondent's preliminary objection on locus standi, grounded in an allegation of mental incapacity, was disallowed on the basis that incapacity is a factual question requiring evidence, not a matter for a preliminary objection. The petition itself, however, was struck out on a separate, cleaner ground: clear statutory processes existed under the Mental Health Act, the Kenya Medical Practitioners and Dentists Act, and the Data Protection Act, all of which had to be exhausted before the constitutional door opened.