1. By consent of both sides, all the writ petitions are taken up for final disposal.

2. Since the issue involved in all these cases are one and the same, all the writ petitions are disposed of by this common order.

3. The common prayer in all these writ petitions are for issuing a writ of mandamus directing the respondent to treat the petitioners as passed in the Group-I Services Preliminary Examinations 2006-2007 conducted by the respondent on 212. 2007 by rectifying the wrong key answers assigned to question Nos.118, 133, 140, 143, 152, 167 & some other questions and permit them to write the Group-I main written examinations scheduled to be held on 18. 2008 and 18. 2008.

4. The facts in nutshell that are necessary for disposal of all these writ petitions are as follows:

.(a) The case of the petitioners in all the writ petitions is that the respondent TNPSC issued a notification on 8. 2007 and invited applications for direct recruitment to the vacancies for the posts included in Group-I Services 2006-2007. The said notification was issued after a gap of seven years. Total number of vacancies notified are 178, distributed among posts in various categories. Petitioners applied for the said posts and also appeared in the preliminary examination (screening test) conducted from 112. 2007 to 212. 2007, according to their optional subjects.

.(b) For Group-I Services, selection procedure consists of three stages viz., Preliminary Examination (Short listing), Main Written Examination and Oral Test. The preliminary examination is a screening test based on objective type questions i.e., to choose the best answers out of the given four options. The respondent has to call for candidates at 1:10 ratio for appearance in the main written examination from various categories. The main written examination is a written test containing General Studies Paper-I and Paper-II. The successful candidates in the main written examination are called for the oral interview for final selection. The selection list will be announced based on the combined marks secured in the main written examination and oral test. Posts are allotted according to the descending order of merit in accordance with the preference given by the candidates in their application.

(c) The preliminary examination results were declared on 24. 2008. In the preliminary examination 200 objective type questions were asked. Each question carries 1.50 marks and the total marks are 300. The cut-off marks fixed for each category and the actual marks obtained by the petitioners in all these writ petitions are as follows:

TABLE

.(d) It is the specific case of the petitioners that the marks awarded to them are lesser than the expected marks, which according to the petitioners is due to the wrong key answers given for some questions as well as wrong questions asked and more than one answer is correct in certain questions. According to the petitioner in W.P.No.12127 of 2008, he submitted a representation on 24. 2006 and pointed out some controversial questions, where the Commission would have given wrong key answers, supported with evidence and even submitted the relevant text books. Immediately after the examination is over, several candidates made representations to the Commission stating similar allegations and discrepancies in the questions as well as answers. However, the Commission failed to rectify the mistakes. According to the petitioners, the Commission should have rectified the discrepancies in the questions/answers by referring the same to the experts in the field/subject or area concerned and proceeded with the valuation and awarded marks as per the correct key answers and award marks to the petitioners, who attended the questions, which are wrongly asked or more than one answer is correct. Following are the sample questions in which there were discrepancies pointed out by the petitioner in W.P.No.12127 of 2008:

"(a) In Question No.118

Consider the following statements:

As