In the last 30 years or so many changes have occurred to not only the structure, but also to the scope of Judicial Review, thereby constructing the contemporary system of judicial review that is in place in England and Wales today. Many of these changes and reforms that have occurred have been due to reports, such as the 1977 and 1994 Law commission reports1, and the Justice-All Souls review, published in 1988. Significant changes have also occurred due to the courts changing perception of Judicial Review in the light of its enlarging scope and importance in administrative law.
Perhaps one of the principle changes that occurred was the 1977 reform of Order 53, which is also given statutory recognition in section 31 of the Supreme Court Act 1981. Prior to 1977 there were separate procedures where applying for one of the prerogative remedies (such as certiorari, mandamus and prohibition), which was commenced by the old Order 53 procedure, and when applying for either a declaration or injunction, via a writ (i. e. challenging the decision via private law). The legal divide between the different remedies, was criticized by many, including Richard Gordon Q.
C. as being "... artificial. It meant that different standing rules applied according to the procedure employed. If the applicant sought a prerogative order locus standi was wider since special damage or infringed private law rights were never necessary constituents of proving an interest under the old O. 53"2. The division of remedies pre-1977 represented an inflexible approach to Judicial Review, which denied applicants certain remedies that may have been more appropriate to their case. Certain procedural differences also existed at this time.
No automatic right was given to cross examination, interim relief or discovery of documents when applying for a prerogative order, whereas this existed in an action for an injunction or a declaration. There were also differences between the time limits allowed for an ordinary action and those allowed for one of the prerogative orders, the latter being more stringent, (a six-month limit for certiorari. ) These artificialities caused concern to many, including the Law Commission, which published its recommendations on possible reform for Judicial Review in 1976.
Without listing all the recommended reforms, it is possible to say that all of the procedural reforms suggested were implemented by the new Order 53 and following this the Supreme Court Act 1981, except the call for interim declarations. The principle reform was that of providing the full availability of all five remedies, under the one umbrella of Order 53 "Applications for Judicial Review"3, thus providing the court with a higher degree of flexibility in the remedies that could be granted.
In relation to locus standi, the test was revised to whether the applicant has "sufficient interest in the matter to which the applicant relates"4. This greatly relaxed the requirement of standing; therefore allowing a number of previously excluded people and groups the possibility of challenging a decision through Judicial Review. However certain uncertainties still exist in relation to the courts implementation of the "sufficient interest" test, which are discussed later.
Returning to the issue of the 1977 reforms, in addition to the above, a provision was made for the disclosure of documents, cross examination and interrogatories (order 53, r. 8(1)), which provided the applicant with an obvious advantage over the pre-1977 Order 53 procedure. It should be noted that the reforms did not bring about absolute rights in many of the provisions, including r. 8(1) (the discovery of documents, etc), but in fact provided the courts with a discretion. In Errington v Wilson  SLT 1193, this issue of when to allow cross-examination was considered.
It was decided that the principles of natural justice must be adhered to, and as there were differences between experts on important points, it was a breach of natural justice to not allow cross-examination. Another of these discretions was that of allowing the applicant's proceedings to continue as if they had begun by writ (r. 9(5)), where it occurs that the case is better dealt with in a private law context. This discretion is of great importance, especially where the distinction between public and private law is indistinct.
The use of this discretion was discussed by Lord Diplock, in the much criticised case of O'Reilly v Mackman  2 AC 237. This case introduced the Exclusivity principle, being that Public and Private law should be kept distinct, and that by allowing a person to in an action begun by writ to continue as if he had applied via Order 53, would "be contrary to public policy, and as such an abuse of the process of court"5. This principle seems to be somewhat artificial, especially in the context of Judicial Review, where, as stated previously the distinction between public and private law is not clear-cut. Professor Wade states, "...
it caused many cases, which on their merits would have succeeded, to fail merely because of choice of the wrong form of action. "6 O'Reilly was also criticised by the Justice-All Souls report, published in 1988, where the House of Lords was asked to reconsider their decision. 7 Matthew Holt argues, "... much of the problem with exclusivity was that a doctrine intended to ensure that public bodies received procedural protections in appropriate cases, became over used by those same bodies. Exclusivity became an attractive "knock out" point to raise in writ proceedings, whether or not the process of the court was being abused by the Plaintiff".
In recent times the Lords have taken a more liberal approach to the Exclusivity principle, such as in Trustees of the Dennis Rye Pension Fund v Sheffield City Council  4 All ER 747, where, "As long as it caused no hardship to the parties, the public or the court, cases could be transferred off and onto the Crown Office list as appropriate where the wrong action was brought. "9. However it is arguable that the Exclusivity principle could be challenged under the Human Rights Act 1998, for non compliance with the convention right to a fair hearing (Article 6).