The meaning and interpretation of sustainable development in the planning framework: Humpty Dumpty has his say

The National Planning Policy Framework was adopted in March 2012, promoting sustainable development as a 'golden thread' running through the whole document. Since then, the concept of sustainable development has been a key or sole consideration in the determination of applications for planning permission. This research is a detailed consideration of that concept within and without the Framework. The research begins by identifying the traditional understandings of the term from its use in international and national policy documents since 1972. It continues with an examination of sustainable development in the Framework to see if a meaning can be derived from analysing its language or from a detailed review of decisions taken where it is applied as a criterion. The research includes a comparative analysis of relevant planning appeal decisions and court judgments in the twenty months from formal adoption of the Framework. Neither the appeal decisions nor the court rulings enable any reliable conclusions to be drawn on what sustainable development means within the Framework. They do show that the Secretary of State has an almost unfettered discretion to decide the meaning of sustainable development on a case by case basis without regard to its interpretation and definitions outside the Framework. Sustainable development has no formally agreed or legally enforceable definition. Unless and until such a definition is secured, the Secretary of State and the courts will assign mutating meanings to the term on a case by case basis.