We may examine the principles of judicial review evolved in the field of administrative law. As has been stated by Lord Brightman in Chief Constable of the North Wales Police v. Evans [1982] 3 All ER 141, “judicial review, as the words imply, is not an appeal from a decision, but a review of the manner in which the decision was made”. In other words, judicial review is concerned with reviewing not the merits of the decision but the decision-making process itself. Lord Diplock in Council of Civil Service Unions v. Minister for the Civil Service (1985) AC 374 at 408, has enunciated three heads of grounds upon which administrative action is subject to control by judicial review, viz., (i) illegality, (ii) irrationality and (iii) procedural impropriety. He has also stated there that the three grounds evolved till then did not rule out that “further development on a case by case basis may not in course of time add further grounds” and has added that “principle of proportionality” which is recognised in the administrative law by several members of European Economic Community may be a possible ground for judicial review for adoption in the future. It may be stated here that we have already adopted the said ground both statutorily and judicially in our labour and service jurisprudence. Lord Diplock has explained the three heads of grounds. By “illegality” he means that the decision-maker must understand correctly that law that regulates its decision-making power and must give effect to it, and whether he has or has not, is a justiciable question. By “irrationality” he means unreasonableness. A decision may be so outrageous or in defiance of logic or of accepted moral standards that no sensible person who had applied his mind to the question to be decided, could have arrived at it, and it is for the judges to decide whether a decision falls in the said category. By “procedural impropriety” he means not only failure to observe the basic rules of natural justice or failure to act with procedural fairness, but also failure to observe procedural rules that are expressly laid down in the legislative instrument by which the Tribunal’s jurisdiction is conferred even where such failure does not involve any denial of natural justice. Where the decision is one which does not alter rights or obligations enforceable in private law, but only deprives a person of legitimate expectations, “procedural impropriety” will normally provide the only ground on which the decision is open to judicial review.