Presumptive Deference and the Role of Expertise on Questions of Law in Canadian Administrative Law

Administrators in Canada are presumptively accorded deference on questions of law. This deference is grounded largely in expertise, a pragmatic justification for deference. This thesis examines the relationship of expertise to other practical justifications for deference and to legislative intent. This thesis questions (i) whether assumptions about administrative expertise are grounded in administrative realities; (ii) whether deference to expertise has a meaningful nexus with legislative intent; and (iii) whether heavy reliance on expertise leaves meaningful room for judicial review on questions of law within reasonableness. I conclude that the doctrine of deference relies too heavily on presumptions about the expertise of administrators on questions of law. Deference of this nature risks allowing administrators to deviate from legislative policy, privileging administration over democracy. Where the courts apply reasonableness, expertise also risks becoming a presumptive explanation for why a decision is reasonable.