The immigration rules started life in the early 1970s as a 17-page document. They now number more than 1,100 pages.

One senior judge said the rules have “achieved a degree of complexity which even the Byzantine Emperors would have envied”.

The Law Commission of England and Wales is consulting on Simplification of the Immigration Rules, and the Faculty agreed in a response that there was a need for an overhaul. It suggested the primary cause of the increased length and complexity had been ever greater prescriptiveness.

“The length of the rules is not necessarily a difficulty in itself…that the Rules should be easy to navigate and understand is more important,” said the Faculty.

“We do not take the view that prescriptiveness is always a difficulty, nor do we take the view that it is always desirable. In some areas, prescriptive rules will allow precise applications to be made (and defective decisions in those areas to be challenged more effectively). In other areas…balancing numerous factors cannot be done satisfactorily within highly prescribed Rules: a more holistic approach is required that a prescriptive system does not allow.”

The Faculty believed that the current state of the law might not meet the requirements of the European Convention on Human Rights and involved reputational risk for the UK. The law had to be accessible and precise, but the Faculty “has concerns whether either of the requirements of lawfulness is met.”

The response added: “We consider that this is a powerful consideration in favour of the comprehensive redrafting proposed and a significant non-monetary benefit of the proposal.

“The Faculty is concerned that the likely cost of the comprehensive redrafting that it supports may not be adequately set out in the impact assessment. The current state of the law is either a result of a lack of resources or of misplaced effort. In either event, a substantial reorganisation is likely to be required to put new Rules in place and maintain a consistent regime…we are not convinced that the proposed review committee of unpaid volunteers will be an adequate mechanism with which to secure the necessary outcomes.”