Judges are not and cannot be experts in all fields and they must exercise great restraint in interfering with the opinion of experts, the Supreme Court said on Thursday while refusing to stay the Uttar Pradesh Public Service Commission (UPPSC) mains examination slated to be held on June 18. The top court said judges cannot take on the role of experts in academic matters and unless the candidate demonstrates that the key answers were patently wrong, the courts cannot enter into this field. A vacation bench of justices U U Lalit and Deepak Gupta set aside the Allahabad High Court's March 30 order by which it had directed for re-evaluation of answer sheets of the preliminary examination for upper-subordinate services in Uttar Pradesh. "When there are conflicting views, then the court must bow down to the opinion of the experts. Judges are not and cannot be experts in all fields and, therefore, they must exercise great restraint and should not overstep their jurisdiction to upset the opinion of the experts," the bench said while dismissing a batch of petitions of students seeking stay of the mains examination. It said the law was well settled that onus was on the candidate to not only demonstrate that the key answer was incorrect, but also that it was a glaring mistake on the face of it and no inferential process or reasoning was required to show that the key answer was wrong. "Judges cannot take on the role of experts in academic matters. Unless, the candidate demonstrates that the key answers are patently wrong on the face of it, the courts cannot enter into the academic field, weigh the pros and cons of the arguments given by both sides and then come to the conclusion as to which of the answer is better or more correct," it said. The bench said that constitutional courts must exercise great restraint in such matters and should be reluctant to entertain a plea challenging the correctness of key answers. Referring to a 1983 verdict, it said the court had recommended a system of moderation, avoiding ambiguity in the questions and prompt decisions be taken to exclude suspected questions and no marks be assigned to such questions. It noted that UPPSC even before publishing the first list of answer keys got it moderated by two expert committees and invited objections, which were also examined by a 26-member expert committee. It said that the 26-member expert committee after examining the objections had recommended that five questions needs to be deleted and in two questions, key answers should be changed. The court said that all the questions needed a long process of reasoning and the high court itself has noticed that the stand of the commission is also supported by certain text books. "In view of the above discussion we are clearly of the view that the high court over stepped its jurisdiction by giving the directions, which amounted to setting aside the decision of experts in the field," it said, setting aside the order of the high court. On June 12, the apex court had said the sanctity of an examination would be lost if courts through their power of judicial review keep interfering with the decisions taken by authorities conducting competitive tests. The top court said a line needs to be drawn to determine to what extent a judicial review can be allowed of the decisions taken by authorities conducting the examinations. The top court's order came on an appeal filed by the UPPSC and pleas of students who have alleged that answers to several questions asked in the commission's preliminary examination held last year were "incorrect". They also said that the UPPSC has not followed the Allahabad High Court's March 30 order directing for re-evaluation of answer sheets of the preliminary test. The mains examination, which was postponed earlier, is now scheduled to be held on June 18. The UPPSC is conducting the examination for 677 posts of upper-subordinate services of the state for which advertisement was issued on February 2017. The preliminary examination for 677 posts was conducted in September 2017.