16. Illegality
Titles in the Complete series combine extracts from a wide range of primary materials with clear explanatory text to provide readers with a complete introductory resource. This chapter examines ‘illegality’ as a ground for judicial review. Central to judicial review is the idea of ultra vires, which is the principle that public authorities have to act within their legal powers and that if they act or fail to act consistently with their legal powers, they will be acting unlawfully. Case law on the exercise of discretionary powers by public authorities is discussed in depth. In addition, the public-sector equality duty in section 149 of the Equality Act 2010 is explained. The concept of jurisdiction and the distinction between error of law and error of fact are also included under this ground of review.