Horizontal Effect and the Constitutional Constraint

This article offers a new interpretation – the ‘constitutional constraint’ model – of the duty the Human Rights Act imposes on the courts to give horizontal effect to European Convention rights through the common law. The model requires courts to develop the common law compatibly with the Convention, but only where compatibility can be achieved by incremental development. We argue that models requiring more than incremental development are unsustainable; that deep constitutional norms compel the constraint of incrementalism, which is preserved under the HRA; and that by virtue of section 2 of the HRA, Convention rights function as principles rather than hard-edged rights in this context. This further undermines the idea that the courts must strictly apply Convention rights and cannot allow them to be overridden by non-Convention factors. The final section explores the nature of incrementalism in this context and the impact of the model on the doctrine of judicial precedent.