Anantanaryanan, J.- This Writ Appeal and the related proceedings (C.M.P. No. 2661 of 1964) for the raising of additional grounds in appeal, have now been segregated by us, from a group of writ appeals and proceedings in which the same questions of importance are involved, following the judgment of the Supreme Court in B. Rajagopala Naidu v. The State Transport Appellate Tribunal, Madras and others1 By virtue of that judgment, it has now been held that G.O. No. 1298 of the Government of Madras, dated 28th April, 1956 is outside the scope of section 43-A of the Motor Vehicles Act, to the extent to which that impugned order seeks to issue directions to the quasi-judicial Tribunals which might fetter or influence their discretion in the grant of stage carriage permits. As their Lordships themselves have observed, the impugned order was issued as early as 1956, and its validity was not impeached in judicial proceedings till the present occasion ; indeed, dicta are to be found’ in such decisions as R. Abdulla Rowther v. The State Transport Appellate Tribunal, Madras and others2, to the effect that, though the instructions were executive and not statutory they were certainly binding upon the Tribunals which were expected to comply with them upon the administrative principle of guidance to subordinate bodies. The very important question that has now arisen for determination relates to the effect of the judgment in (C.A.No. 19 of 1964)1upon the decisions of the statutory bodies prior to that judgment, when the Government Order was taken as valid by all authorities concerned and by this Court itself, and decisions of single Judges of this Court in a similar context, now pending in this group of Writ Appeals. The matter might be expressed in the following form. One main argument pressed for the respondents is that, since the instructions in the Government Order were presumed to be valid and binding on the statutory Tribunals, upon the principle of administrative guidance, these decisions canvassed in writ proceedings cannot be said to embody any error of law manifest upon the record ; the law was correctly applied, as then understood, at all levels. Another argument is that, even on the assumption that decisions based on the Government Order, directly or indirectly, may have to be now struck down by the issue of a writ of certiorari or other appropriate writ, this cannot be said to apply to all instances. There may be instances where the “compulsive force of the impugned order” (vide judgment in Rajagopala Naidu’s case1) may not be manifest, and the decision might primarily be upon other grounds. We might immediately state that these same points were also considered, in some detail, in the Bench decision of this Court in W.A. No. 74 of 1964. We first propose to deal with these substantial grounds, relating to the effect of the judgment of the Supreme Court in Rajagopala Naidu’s case1 on these pending appeals. There is a separate ground which relates exclusively to C.M.P.No. 2661 of 1964, and which equally applies to other proceedings of that character in concerned writ appeals. This ground is that, in any event, a party who seeks relief in a Letters Patent Appeal, with reference to the exercise of the powers of this Court under Article 226 of the Constitution, and ex debito justitiae, cannot here raise for the first time the ground of invalidity of the decision because of the impugned Government Order. Having submitted to the jurisdiction of the State Transport Appellate Tribunal in that respect, without pleading that ground, and having invited an adjudication upon the very directions of the Government Order, and further not having advanced such a contention even before the learned single Judge, who disposed of the Writ Petition, any such party is wholly excluded from advancing the ground in the appeal. This is a separate matter, clearly determinable within its own scope, in the light of the authorities placed before us. We shall proceed to it in due course. We shall immediately deal with the argument of Sri Tiruvenkatachari for respondents, which would apply to other parties similarly situate in the other Writ Appeals, that, since the statuory Tribunals or the learned single Judge, as the case may be, correctly applied the law as then understood, there can be no manifest error of law in the decisions of the Tribunals, purely because the Government order was followed and applied. In this context, it is important to note the reasoning upon which the Government Order was struck down in C.A. No. 19 of 1964,1 and the following passage is vital in that context. Their Lordships observed: "In interpreting section 43-A, we think, it would be legitimate to assume that the Legislature intended to respect the basic and elementary postulate of the rule of law, that, in exercising their authority and in discharging their quasi-judicial function, the Tribunals constituted under the Act must be left absolutely free to deal with the matter according to their best judgment. It is of the essence of fair and objective administration of law that the decision of the Judge or the Tribunal must be absolutely unfettered by any extraneous guidance by the executive or administrative wing of the State. If the exercise of discretion conferred on a quasi-judicial tribunal is controlled by any such direction, that forges fetters on the exercise of quasi-judicial authority, and the presence of such fetters would make the exercise of such authority completely inconsistent with the well-accepted notion of judicial process." Their Lordships later enunciated the true doctrine of repugnancy between the impugned Government Order and the decision of the Tribunal itself as follows: "If the Appellate Transport Authority had considered these matters on its own without the compulsive force of the impugned Order, it would have been another matter ; but the order pronounced " by the Appellate Authority clearly and unambiguously indicates that it held, and in a sense rightly, that it was, bound to follow the impugned Order ; .................... Therefore, we have no. hesitation in holding that the decision of the Appellate Tribunal is based solely on the provisions of the impugned Order and since the said Order is invalid, the decision itself must be corrected by the: issue of a writ of certiorari." It has to be very carefully noted that the observations in Abdulla’s case 2, are not in conflict with the principle enunciated in the above passages, in any sense. On the contrary, as their Lordships themselves pointed in C.A. No. 19 of 1964,1 what that decision held was that the directions issued under section 43-A were merely executive or administrative in character, and their breach, even if patent, would not justify the issue of a writ. On the contrary, as their Lordships themselves pointed in C.A. No. 19 of 1964,1 what that decision held was that the directions issued under section 43-A were merely executive or administrative in character, and their breach, even if patent, would not justify the issue of a writ. To quote: "The executive orders properly so-called, do not confer any legal enforceable rights on any persons and impose no legal obligations on the subordinate authorities for whose guidance they are issued ; that is not to say that the directions are not valid and should not be followed by the said authorities ; the said authorities are undoubtedly expected to follow the said directions and their breach may expose them to disciplinary or other appropriate action. If the present Government Order is held to be an executive order, it would confer no legal and enforceable rights on any applicant for permits...................." Therefore, we think that the situation is clear, and we are unable to see any conflict between the law as laid down earlier, and the decision1 of Supreme Court in C.A. No. 19 of 1964. The point about the validity of the impugned order, with reference to its inconsistency with section 43-A did not arise for decision in Abdulla’s case2. The observations made in that case, concerning the duty of the Tribunals to follow those directions, which were held to be purely executive in character upon the administrative principle or canon of the liability of subordinate bodies to be guided in administrative matters, really do not bear upon the principle now enunciated. Of course, it is true that every concerned authority, including the High Court, laboured under the impression that the Government Order was valid. But the fact that the law was misunderstood then, cannot make the decision based upon such misapprehension, any the lesss an error of law manifest on the record. In Prem Sagar v. Messrs. Standard Vacuum Oil Company, Madras and others1, the Supreme Court had recently occasion to consider the scope of this matter viz., the true principle of the issue of certiorari to correct an error of law. The Supreme Court observed: “In fact, after the judgment of this Court was pronounced in the case of Parry &38; Co. Standard Vacuum Oil Company, Madras and others1, the Supreme Court had recently occasion to consider the scope of this matter viz., the true principle of the issue of certiorari to correct an error of law. The Supreme Court observed: “In fact, after the judgment of this Court was pronounced in the case of Parry &38; Co. Ltd.2 the question about the jurisdiction of High Courts in issuing writs of certiorari under Article 226 has been frequently considered, and there is consensus of opinion in the judgments delivered by this Court ever since that a writ of certiorari can be issued where the order of the inferior tribunal is shown to suffer from an error which is apparent on the face of the record.......... It is, of course, difficult and indeed it would be inexpedient to lay down any general test to determine which errors of law can be described as errors of law apparent on the face of the record...............” In Syed Yakoob v. Radhakrishnan3, their Lordships observed: “Where it is manifest or clear that the conclusion of law recorded by an inferior Court or Tribunal is based on an obvious mis-interpretation of the relevant statutory provision, or sometimes in ignorance of it, or may be, even in disregard of it, or is expressly founded on reasons which are wrong in law, the said conclusion can be corrected by a writ of certiorari.......... It may also be that in some cases, the impugned error of law may not be obvious or patent on the face of the record as such, and the Court may need an argument to discover the said error ; but there can be no doubt that what can be corrected” by a writ of certiorari is an error of law, and the said error must, on the whole, be of such a character as would satisfy the test that it is an error of law apparent on the face of the record." Immediately after this, their Lordships referred to the possibility of two reasonable constructions which a statute might admit, and Sri Trivenkatachari presses this passage into his argument that it was reasonable for the statutory bodies, as the law was then interpreted, to consider the Government Order as valid. But this argument is clearly unacceptable. But this argument is clearly unacceptable. We must hold that the Government Order is outside the purview of section 43-A, and invalid for that reason, and that that has always been the case ; the exposition of the law makes for no departure in this respect ; indeed, the issue was never raised earlier. Hence, our conclusion must be that, in all these appeals, where the Government Order has been, directly or indirectly, the basis of decision, or One important factor of decision, there is a manifest error of law which justifies the issue of the writ. Discussing the same matter, in W.A. No. 74 of 1964,4 Srinivasan, J., delivering the Judgment on behalf of the Bench, observed that the mere existence of such directions by Government, which the Tribunals thought to be binding on them, would sufficiently indicate their influence, and that this Court cannot hence embark” upon the wholly futile task of differentiating between such cases. “Latter, the learned Judge expressed the applicable criterion in the form that "so long as the decision by the quasi-judicial Tribunal was brought about by reliance upon the invalid Government Order, there was no judicial disposal of the matter at all." As the learned Judge has observed, the Government Order itself expressly permitted the Tribunals not to apply the marking system contained therein, if, for reasons to be recorded, the Tribunal thought that the decision ought to be based upon some principle of preference outside this system. If there are such cases, of course, they would not be affected by the judgment of the Supreme Court in C.A. No. 19 of 1964.5 Even in other cases, we think it is conceivable that there may be instances, where the directions contained in the Government Order have not been operative at all; for instance, as between two rival claimants, one might have been excluded by the State Transport Appellate Tribunal, upon some other principle of law, and not with reference to assessment of claims under the marking system. But outside all such cases, and we concede that the mere citation of the Government Order in some part of the judgment may not, by itself, be conclusive, it will be a matter of fact, upon the merits of each case, whether the Government Order has been, so to speak, an important operative influence. But outside all such cases, and we concede that the mere citation of the Government Order in some part of the judgment may not, by itself, be conclusive, it will be a matter of fact, upon the merits of each case, whether the Government Order has been, so to speak, an important operative influence. If such a thing exists, it will certainly be sufficient to vitiate the disposal, and the words of their Lordships "the compulsive force of the impugned Order" need not be interpreted to mean the judgment must be entirely exclusively based upon the directions in the Government Order, and upon nothing else. This, in our view, will be the proper criterion to apply. Each case, naturally, will have to be dealt with upon its merits, in a separate manner. Before proceeding to C.M.P. No. 2661 of 1964, there are two other points urged by Sri Tiruvenkatachari for the respondents and also by Sri Kumaramangalam, which might be now referred to. The first is that a party cannot seek this relief ex debitio justitiae, having himself not merely failed to impugn the Government Order, but having even invoked it, and stood by the instructions, in submissions before the statutory body. This doctrine of acquiescence is really more relevant to the question of allowance or disallowance of the additional ground of appeal, but it has also application to the main argument itself. It is urged that this is not a question of jurisdiction. At the highest for the appellant, this is a question of extraneous matter, which has been permitted to influence the Tribunal in such a way that it amounts to a manifest error of law. Here, we think that certain observations from Ade Smith’s ‘Judicial Review of Administrative Action’ quoted by Rajamannar, C.J., in S. M. Transport v. Raman and Raman1, are very pertinent. Here, we think that certain observations from Ade Smith’s ‘Judicial Review of Administrative Action’ quoted by Rajamannar, C.J., in S. M. Transport v. Raman and Raman1, are very pertinent. It is observed in that passage as follows: "If the influence of irrelevant factors is established, it does not appear to be necessary to prove that they were the sole or even the dominant influence ; it seems to be enough to prove that their influence was substantial." It is for this reason that we have stated that the principle cannot be that the Government Order must have been the sole and exclusive basis of the decision of the Tribunal, and, as Srinivasan, J., has observed, the disposal itself will not be a judicial disposal, if the directions in the Government Order have been the major influencing factor on the decision. It is only in cases where the operation of the Order has been expressly excluded, or where the decision is manifestly upon some principle outside the ambit of the Order, that the issue of the writ will not be appropriate. Further, the fact that the party laboured under ignorance of the law, and even invoked the erroneous application of the law, cannot preclude him from obtaining relief. This is because the discretion of this Court under Article 226, is not merely the individual right of any party ; it can be exercised in public interest, of course in appropriate proceedings, such as where the quasi-judicial functions of a statutory body have been affected by an improper invasion of executive directions. The other point argued is that, logically, it should follow that we must set aside not merely the decision of the State Transport Appellate Tribunal, but the grant by the Regional Transport Authority in every case, since that has been the root of the error. This was considered in W.A. No. 74 of 1964,2 and the learned Judges rejected it mainly upon the "very serious public inconvenience" which would thereby caused, apart from the doubt regarding the jurisdiction of this Court to interfere with an order of the Regional Transport Authority, which is not properly before the Court. This was considered in W.A. No. 74 of 1964,2 and the learned Judges rejected it mainly upon the "very serious public inconvenience" which would thereby caused, apart from the doubt regarding the jurisdiction of this Court to interfere with an order of the Regional Transport Authority, which is not properly before the Court. On this aspect, we think it is sufficient to observe that, where the case is sent back to the State Transport Appellate Tribunal, it necessarily implies that the grant by the Regional Transport Authority in favour of whichever party it might be is equally subject to the fresh disposal outside the influence of the impugned Government Order, which has to be now made ; this obviates any need for formally setting aside the grant by the Regional Transport Authority, in any particular case. We may immediately proceed to dispose of the point relating to the admissibility of the fresh ground raised in C.M.P. No. 2661 of 1964. The contention of Sri Kumaramangalam is here a very simple one. The party who invoked the Government Order not merely in the proceedings before the State Transport Appellate Tribunal but even before the learned Judge (Srinivasan, J.) stood by it, precisely as the opposite party did, since the proceedings were all of them prior to the judgment of the Supreme Court in, Rajagopala Naidu v. S.T. A. T., Madras3 and the validity of the impugned Order, with reference to section 43-A, was not conceived or raised. There are other such instances, in this group of Writ Appeals Sri Kumaramangalam does not express it as a matter of jurisdiction, but he does contend that this Court, in its discretion, may well prevent the party from raising the issue now. In Lakskmanan Chettiar v. Commissioner of Corporation of Madras1 this Court held that it has discretion not to permit a party to raise a ground or objection as to jurisdiction, not taken before the subordinate Tribunal; this was on the principle of Rex v. Williams2, and other English decisions. It is noteworthy that in Pannalal Binjraj v. Union of India3 their lordships of the Supreme Court similarly held that where a party had acquiesced in the jurisdiction of a subordinate authority (Income Tax Officer) he could not again question that jurisdiction under Article 32 of the Constitution ; Lakskmanan Chettiar v. Commissioner of Corporation of Madras1, was approbated. It is noteworthy that in Pannalal Binjraj v. Union of India3 their lordships of the Supreme Court similarly held that where a party had acquiesced in the jurisdiction of a subordinate authority (Income Tax Officer) he could not again question that jurisdiction under Article 32 of the Constitution ; Lakskmanan Chettiar v. Commissioner of Corporation of Madras1, was approbated. Learned Counsel contends that the case is stronger, where it is a matter of a Letters Patent Appeal from the Judgment of a single Judge. In Hussain Bai v. Motilal4, it was observed that where a case was decided by a single Judge, it is his judgment which is the subject-matter of the appeal under Clause 10 of the Letters Patent. Also see the dicta of a Bench of the Bombay High Court in Nagappa v. Ramchandra5. The matter was considered upon these relevant aspects by Kailasam, J., in the Full Bench decision in W.A. No. 215 of 19626. In Messrs. Gandhinagar Motor Transport Society v. Shri Kasbekar7 Chagla, C.J., followed Rex v. Williams2, and held that, where the jurisdiction, of the inferior Tribunal was not challenged, relief could not be asked for upon that ground in writ jurisdiction. But there is one very important exception to this general principle, and it is on this exception that the doctrine of acquiescence was not held to apply to facts of this character, and the party was specifically permitted to raise the ground. The rule or principle itself, and the exception thereto, are both clearly expressed in the following passage in A. T. Markose’s Judicial Control of Ad ninistrative Action in India (1956 Edition) page 476: "An aspect of the doctrine of acquisence is seen in the rule, that if a party, armed with either a point of law or fact, which would oust the jurisdiction of the inferior tribunal, abstains from raising it before that tribunal on the hope of a favburable decision he is precluded from brandishing it before the superior Court to attack the decision of the lower tribunal. A person who has a ground which ousts the jurisdiction of the inferior tribunal and who elects to keep it by, and argues before the tribunal the merits of his case, must be taken to have submitted to its jurisdiction. A person who has a ground which ousts the jurisdiction of the inferior tribunal and who elects to keep it by, and argues before the tribunal the merits of his case, must be taken to have submitted to its jurisdiction. This rule, is not applicable, if the ground he urges before the certiorari Court was not known to him at the time when the matter was before the inferior tribunal. The affidavit should state this matter of ignorance upon this aspect of an ignorance or misapprehension on a question of law, which might be shared by the Court itself we may also refer here to Mahabir v. Narain8. The very important principle of ignorance upon an aspect of law, not adversely affecting the right of a party to raise a fresh ground because of acquiescence, was. dealt with by Rajamannar, C.J., in Arunachalam v. Southern Roadways9. The Supreme Court affirmed this decision, and agreed with this view in Arunachalam Pillai v. Messrs. Southern Roadways Ltd.10. These passages are set out by Kailasam, J., in the Full Bench decision in W.A. No. 215 of 19626 and we need not, therefore, reproduce them here. It is sufficient to say that Rajamannar, C.J., expressed it thus: "A person who has no knowledge of his right and is not guilty of culpable negligence in being ignorant, will not be denied a relief to which he is entitled on the ground that he omitted to assert that, right." Sri Kumaramangalam contends that the present ground is not even a ground of jurisdiction, but is a ground of intrusion of extraneous material. But as we saw earlier, this intrusion does amount to a manifest error of law and, actually, as observed by Srinivasan, J., in W.A. No. 74 of 1964 it takes away the judicial character of the disposal altogether. Such a ground could not have been raised at an earlier stage by any party either before the statutory Tribunal, or even before the learned single Judge of this Court, for the reason that the Law was not then understood as affecting the validity of the Government Order; the inconsistency between section 43-A and the directions in the Government Order had not been mooted at all in a judicial proceeding, nor had any decision been obtained thereon. That was an ignorance of the law shared by parties, statutory bodies and Courts alike and we are clearly of the view that this will not preclude a party, like the appellants from raising it as an additional ground of appeal. C.M.P. No. 2661 of 1964 is allowed and this Writ Appeal and the other Writ Appeals of this group together with the concerned applications in them, will now be taken up for disposal in the light of these observations. On further hearing the following order of the Court was made by Anantanarayanan, J.- In continuation of the judgment already delivered by us in these proceedings (W.A. No. 6 of 1963 and C.M.P. No. 2661 of 1964) upon the crucial issues that we took up for determination, we might state that it is clear from a perusal of the order of the State Appellate Tribunal that G.O. Home No. 2265 dated, 9th August, 1958 (G.O. No. 1298 dated 28th April, 1956) has not merely influenced the decision of the Tribunal, but was substantially one of the basis of that decision vide paragraphs 17 etc. of the judgment. It follows that the appeal will have to be allowed, and the writ issued quashing the order. This will release the proceedings, to be further taken up and disposed of by the State Transport Appellate Tribunal, in the light of our judgment. The parties to the proceedings here who have instituted the appeal will, therefore, have the right to have the matter re-determined in the context of the decision of the Supreme Court and the Judgment of this Court. Ordered accordingly. V.K. ------------- Appeal allowed.