Summarize the following court judgment. Civil Appeal Nos. 708 to 710 Of 1978. Appeals by Special Leave from the Judgment and order dated 18 2 1978 of the Bombay High Court in Special Civil Application Nos. 2564/74	 5997/78 and 5999/78. V.M. Tarkunde	 C.K Ratnaparkhi	 V.N. Ganpule	 Mrs. Veena Devi Khanna and Miss Manik Tarkunde for the Appellants in all the appeals. Soli J. Sorabjee	 S.K Mehta	 P.N. Puri and E.M.S. Anam for the Respondents 1 to 6 in CAs 708 to 710/1978. P.H. Parekh	 C.B. Singh	 B.L. Verma	 Miss V. Caprihan	 Hemant Sharma and Raian Karanjawala for the Respondent No. 5 in CA 710/78. The Judgment of the Court was delivered by CHINNAPPA REDDY	 J. The respondents in Civil Appeal No. 708 of 1978	 Mamanchand Ratilal Agarwal and others	 who are the landlords of premises bearing door No. 16 in Nawa Bazar Area Kirkee Cantonment	 filed civil suit No. 1730 of 1964 against the appellant tenant for recovery of possession and arrears of rent under the provisions of the Bombay Rents	 Hotel and Lodging House Rate Control Act	 1947. The suit was decreed. There was an appeal by the tenant. It resulted in a compromise decree dated July 12	 1967 by which some time was given to the tenant to vacate the premises. As the tenant failed to vacate the premises within the time given to him	 the landlords were compelled to take out execution. On April 29	 1969	 in the case of Indu Bhusan Bose vs Rama Sundari Devi & Anr this Court held that Parliament alone had and the State Legislature did not have the necessary competence to make a law in any regard to the "regulation of house accommodation in Cantonment . areas". The expression "regulation of house accommodation" was interpreted as not to be confined to allotment only but as extending to other incidents	 such as termination of existing tenancies and eviction of persons in possession of house accommodation etc. To get over the situation created by Indu Bhusan Bose vs Rama Sundari Devi & Anr. on December 29	 1969	 the Central Government issued a notification under Section 3 of the 	 extending the provisions of the Bombay Rents	 Hotel and Lodging House Rates Control Act	 1947	 to the Kirkee and other Cantonment areas. On June 2	 1972	 the Parliament also 228 enacted Act 22 of 1972 amending the Cantonments (Extension of Rent Control Law;) Act	 1957	 purporting to enable the Central Government to make the rent control laws in the several States applicable to Cantonment areas from dates anterior to the dates of notification and further purporting to validate certain pre existing decrees. In the meanwhile taking advantage of the decision in the case of Indu Bhusan vs Rama Sundari Devi & Anr. (supra)	 the appellant tenant filed Miscellaneous Application No. 597 of 1970 for a declaration that the decree obtained against him was a nullity and incapable of being executed. This application was allowed by the Court on November 15	 1971. But	 after the enactment of Act 22 of 1972	 on January 11	 1973	 the landlords filed Darkhast No. 104 of 1973 to execute the decree in their favour. The tenant raised various objections. One of the objections was that subsequent to the compromise decree there was a fresh agreement of lease between the landlords and himself. This was denied by the landlords. Another objection was that the provisions of the Amending Act 22 of 1972 were not extensive enough to save the decree dated July 12	 1967. The third objection was that in any case the decision in miscellaneous application No. 597 of 1970 holding the decree to be a nullity operated as res judicata between the parties. The first of the objections was left open by all the Courts for future adjudication. The second and third objections alone were considered	 for the time being. In the judgment under appeal	 the High Court over ruled the second and third objections of the tenant and hence this appeal by special leave. The first question for our consideration is whether the compromise decree dated July 12	 1967 is saved by Amending Act 22 of 1972? Before the decision of this Court in Indu Bhusan Bose vs Rama Sundari Devi & Anr. (supra)	 there was a conflict of views on the question whether Entry 3 of List I of Schedule VII to the Constitution which enabled Parliament to legislate in regard to "the regulation of housing accommodation (including the control of rents)" in Cantonment areas was wide enough to include the subject of relationship of landlord and tenant of buildings situated in Cantonment areas. The High Courts of Bombay	 Nagpur and Patna had taken the view that regulation of the relationship of landlord and tenant did not fall within Entry 2 of List I of the Seventh Schedule to the Govt. Of India Act	 1935 (which corresponded to Entry 3 of List I of Seventh Schedule to the Constitution and that the Provincial Legislature was competent to legislate even in regard to the regulation of the relationship between landlord and tenant in Cantonment areas by virtue of Entry 21 of List II of the 229 Seventh Schedule to the Govt. Of India Act	 1935(which corresponded to Entry 18 of the List II of the Seventh Schedule to the Constitution). On the other hand the High Courts of Calcutta and Rajasthan held that the power of the State Legislature to legislate in respect of landlord and tenant of buildings was to be found not in Entry 18 of List II but in Entries 6	 7 and 13 of List III of the Seventh Schedule to the Constitution and that such power was circumscribed by the exclusive power of Parliament to legislate on the same subject under Entry 3 of List I. The view expressed by the Calcutta and Rajasthan High Courts was accepted as correct by this Court in Indu Bhusan Bose vs Rama Sundari Devi & Anr. (supra)	 But even before the decision of this Court in Indu Bhusan Bose vs Rama Sundari Devi & Anr. (supra)	 Parliament appeared to take view of the Calcutta and Rajasthan High Courts as the correct view and proceeded to enact the 	 by Section 3 of which the Central Government was enabled	 by notification in the official Gazette	 to extend to any Cantonment with such restrictions and modifications as it thought fit. Any enactment relating to the control of rent and regulation of house accommodation which was in force on the date of the notification in the State in which the Cantonment was situated. Though this Act came into force on December 18	 1957	 no notification was issued extending the provisions of the Bombay Rents	 Hotel and Lodging House Rates Control Act	 1947	 to Kirkee and other Cantonment areas within the State of Bombay until 1969. Apparently such a notification was thought unnecessary in view of the fact that the Bombay Act was supposed to operate within the said Cantonment areas because of the consistent view taken by the Bombay High Court	 regarding the applicability of the Bombay Act to such areas. But the position was upset as a result of the decision of this Court in Indu Bhusan Bose vs Rama Sundari Devi & Anr. (supra). Thereafter it became necessary that a notification under section 3 of the Cantonment (Extension of Rent Control Laws) Act	 1957	 should be issued. It was accordingly done on December 29	 1969. But it was soon realised that the entire problem was not thereby solved since all such notification as the one issued on December 29	 1969 could only be prospective and could not save decree which had already been passed. Amending Act 22 of 1972 was	 therefore	 enacted for the express purpose of saving decrees which had already been passed. The statement of objects and reasons of the amending act stated: ". . But these notifications could be issued only prospectively and could not save the decrees already passed. A number of representations had been received 230 from and on behalf of tenants and tenants ' associations	 ventilating their grievances in this regard. It was accordingly proposed to amend section 3 to empower the Government to extend to any Cantonment any enactment relating to the control of rent and regulation of house accommodation in force in the State in which the Cantonment was situated either from the commencement of such enactment or from 26 1 1950	 the date when the Constitution came into force	 whichever was later	 and to save decrees already passed under the enactment deemed to have been in force in the Cantonment before such extension. " By section 2 of the Amending Act of 1972 the Principal Act of 1957 was itself deemed to have come into force on January 26	 1950. Original section 3 was renumbered as sub. section 1 and the words "on the date of the notification" were omitted and "were deemed always to have been omitted". New sub. sections 2	 3 and 4 were introduced and they are as follows: "(2) The extension of and enactment under sub section (1) may be made from such earlier or future date as the Central Government may think fit: Provided that no such extension shall be made from a date earlier than (a) the commencement of such enactment	 or (b) the establishment of the cantonment	 or (c) the commencement of this Act	 whichever is later. (3) Where any enactment in force in any State relating to the control of rent and regulation of house accommodation is extended to a cantonment from a date earlier than the date on which such extension is made (hereafter referred to as the "earlier date")	 such enactment	 as in force on such earlier date	 shall apply to such cantonment	 and where any such enactment	 has been amended at any time after the earlier date but before the commencement of the Cantonments (Extension of Rent Control Laws Amendment Act 1971	 such enactment	 as amended	 shall apply to the cantonment on and from the date on which the enactment by which such amendment was made	 came into force. (4) Where	 before the extension to a cantonment of any enactments	 relating to the control of rent and regula 231 tion of house accommodation therein (hereafter referred to as the "Rent Control Act"): (i) any decree or order for the regulation of	 or for eviction from	 any house accommodation in that cantonment	 or (ii) any order in the proceedings for the execution of such decree or order	 or (iii) any order relating to the control of rent or other incident of such house accommodation	 was made by any court	 tribunal or other authority in accordance with any law for the control of rent and regulation of house accommodation for the time being in force in the State in which such cantonment is situated	 such decree or order shall	 on and from the date on which the Rent Control Act is extended to that cantonment	 be deemed to have been made under the corresponding provisions of the Rent Control Act	 as extended to that cantonment	 as if the said Rent Control Act	 as so extended	 were in force in that Cantonment	 on the date on which such decree or order was made". The effect of the provisions of the Amending Act appear to us lo be very clear. Under section 3 of the unamended Act	 a notification could be issued extending a State Legislation to a Cantonment area with effect from the date of the notification. As a result of the introduction of sub. section 2 of section 3 the notification can be given effect from an anterior date or a future date	 but it cannot be made effective from a date earlier than the commencement of the State Legislation or the establishment of the Cantonment or the commencement of the Cantonment (Extension of Rent Control Laws) Act	 1957. section 3 is merely consequential to sub. section 2 in that it provides that a State Legislation when extended to a Cantonment area from an anterior date	 such legislation is to stand extended with all the amendments to such State Legislation made after such anterior date but before the commencement of the 1972 Amending Act	 the amendments being applicable as and when they come into force. Sub .s. 4 makes provision for the saving of decrees or orders for the regulation of or for eviction from any house accommodation in a Cantonment made before the extension of the State Legislation to the Cantonment provided certain conditions are fulfilled. One condition is that the decree or order must have been made by any Court	 Tribunal or other authority in accordance with a law for the control of rent and regula 232 tion of house accommodation for the time being in force in the State in which such Cantonment is situated. In other words the decree or order must have been made by the wrong application of the State legislation to the Cantonment area. If a decree or order has been made by such wrong application of the State Legislation to the Cantonment area	 it shall be deemed	 with effect from the date of the notification	 to have been properly made under the relevant provisions of the State Legislation. Shri V.M. Tarkunde	 learned Counsel for the appellant urged that sub. section 4 had to be read in the context of sub. section 2 and 3 and that it was to be applied only to cases where a notification issued under sub. section 1 was given retrospective effect under the provisions of sub. section 2. We see no justification for confining the applicability of sub. section 4 to cases where notifications are issued with retrospective effect under sub. section Sub. section 4 in terms is not as confined. It applies to all cases of decrees or orders made before the extension of a State Legislation to a Cantonment area irrespective of the question whether such extension is retrospective or not. The essential condition to be fulfilled is that the decree or order must have been made as if the State Legislation was already in force	 although	 strictly speaking	 it was not so in force. In our view sub. section 4 is wide enough to save all decrees and orders made by the wrong application of a State rent control and house accommodation legislation to a Cantonment area	 though such State Legislation could not in law have been applied to Cantonment areas at the time of the passing of the decrees or order. We	 therefore	 hold that the decree obtained by the respondents is saved by the provisions of section 3	 4 sub. section 4 of the Cantonment (Extension of Rent Control Laws) Act of 1957. as amended by Act 22 of 1972. The second submission of the learned counsel for the appellant was that the decision of the executing Court in Miscellaneous Application No. 597 of 1970 declaring the decree to be a nullity separated as res judicata between the parties. The learned counsel relied upon the following observations of this Court in Mathura Prasad Bajoo Jaiswal & ors. vs Dessibai N.B. Jeejeebhoy(1) "The matter in issue	 if it is one purely of act	 decided in the earlier proceeding by a competent court must in a subsequent litigation between the same parties be regarded as finally decided and cannot be reopened. A mixed question of law and fact determined in the earlier proceeding between the same parties may not	 for the reason	 be questioned in a subsequent proceeding between 233 the same parties. But	 where the decision is on a question of law	 i.e. the interpretation of a statute	 it will be res judicata in a subsequent proceeding between the same parties where the cause of action is the same	 for the expression 'the matter in issue ' in section 11 Code of Civil Procedure means the right litigated between the parties i.e. the facts on which the right is claimed or denied and the law applicable to the determination of that issue. Where	 however	 the question is one purely of law and it relates to the jurisdiction of the Court or a decision of the Court sanctioning something which is illegal	 by resort to the rule of res judicata a party affected by the decision will not be precluded from challenging the validity of that order under the rule of ( ' res judicata	 for a rule of procedure cannot supersede the law of the land. In the very observations relied upon by the learned counsel for the appellant the last sentence is clearly against the appellant. The matter becomes clear if certain observations made earlier in the very judgment are considered. They are: "A question relating to the Jurisdiction of a Court cannot be deemed to have been finally determined by an erroneous decision of the Court. If by an erroneous interpretation of the statute the Court holds that it has no jurisdiction	 the question would not	 lin our judgment	 operate as res judicata. Similarly by an erroneous decision if the Court assumes jurisdiction which it does not possess under the statute	 the question cannot operate as res judicata between the same parties	 whether the cause of action in the subsequent litigation is the same or otherwise". In that case the appellant who had a lease of an open land for construction of buildings had applied for determination of standard rent under the Bombay Rents	 Hotel and Lodging House Rates Control Act	 1947. The application was rejected on the ground that the Act did not apply to open land let for construction. The view was confirmed by the High Court. Later in another case	 the view taken by the High Court was over ruled by the Supreme Court and it was held that the Act applied to open land let out for construction The appellant once again filed an application for determination of standard rent. The lower Courts and the High Court held that the previous decision operated as res judicata between the parties. The Supreme Court reversed the view of the lower courts and the High Court. It 16 189SCI/80 234 was held that the earlier decision that the Civil Judge had no jurisdiction to entertain the application for determination of standard rent ? was wrong in view of the judgment of the Supreme Court. If the decision in the previous proceeding was to be regarded as res judicata it would assume the status of a special rule of law applicable to the parties relating to the jurisdiction of the Court in derogation of the rule declared by the legislature. The situation in the present case is analogous. The executing Court had refused to exercise jurisdiction and to execute the decree on the ground that the decree was a nullity as the Bombay Rents	 Hotel and Lodging House Rates Control Act	 1947	 had no application to buildings in Cantonment areas. That defect having been removed and all decrees obtained on the basis that the Bombay rent law applied to the Kirkee Cantonment area having been validated by Act 22 of 1972	 it cannot be said that the earlier decision holding that the decree was a nullity operated as res judicata. As pointed out by this Court in Mathura Prasad Bajoo Jaiswal & Ors. I vs Dassibai N.B. Jeejeebhoy (supra) if the earlier decision in the Miscellaneous Application is to be regarded as res judicata it would assume the status of a special rule of jurisdiction applicable to the parties in derogation of the law declared by the legislature. We	 therefore	 see no substance in the second submission. Civil Appeal No. 708 of 1978 is accordingly dismissed with costs. In Civil Appeal No. 709 of 1978	 the only question is about the validity of a decree obtained before the date of the notification issued under section 3 of the . In view of what we have said above	 this question has to be decided against the appellant. This appeal is also dismissed with costs. In Civil Appeal No. 718 of 1978	 special leave was granted under a misapprehension that the appeal raised the same questions as were raised in Civil Appeal No. 708 of 1978. It is now stated that it is not so. This appeal is also dismissed with costs. S.R. Appeals dismissed.

The respondents in Civil Appeal No. 708/78 Mamanchand Ratilal Agarwal and others	 who are the landlords of premises bearing door No. 16 in Nawa Bazar Area Kirkee Cantonment	 filed a civil suit No. 17	0 of 1964 against the Appellant tenant for recovery of possession and arrears of rent under the provisions of Bombay Rents	 Hotel and Lodging House Rates Control Act	 1947. The suit was decreed. There was an appeal by the tenant. It resulted in a com promise decree dated July 12	 1967 by which some time was given to the tenant to vacate the premises. On April 29	 1969	 in the case of Indu Bhushan Bose vs Rama Sundari Devi and Anr. ; 	 this Court held that Parliament alone had and the State Legislature did not have the necessary competence to make a law in regard to the "regulation of house accommodation in Cantonment Areas. " The expression "regulation of house accommodation" was interpreted as not to be confined to allotment only but as extending to other incidents	 such as termination of existing tenancies and eviction of persons in possession of house accommodation etc. To get over the situation created by the said decision	 on December 29	 1969	 the Central Government issued a notification under section 3 of the Cantonment (Extension of Rent Control Laws) Act	 1957 extending the pro visions of the Bombay Rents	 Hotel and Lodging House Rates Control Act	 1947	 to the Kirkee and other cantonment areas. In June 2	 1972	 the Parliament also enacted Act 22 of 1972 amending the Cantonment (Extension of Rent Control laws) Act 1957	 purporting to enable the Central Government to make the Rent Control Laws in the several States applicable to Cantonment areas from dates anterior to the dates of notification and further purporting to validate certain pre existing decrees. In the meanwhile	 taking advantage of the decision in the case of Indu Bhushan Bose vs Rama Sundari Devi and Anr.	 the appellant tenant filed Miscellaneous Application No. 597/70 for a declaration that the decree obtained against him was a nullity and incapable of being executed. This application was allowed by the Court on November	 19	 1971. But	 after the enactment of Act 22 of 1972	 on January 11	 1973 the landlords filed Darkhast No. 104 of 1973 to execute the decree in their favour. The appellant tenant raised three objections	 namely	 (i) subsequent to the compromise decree there was a 225 fresh agreement of lease between the landlords and himself; (ii) the provisions of the amending Act 22 of 1972 were not extensive enough to save the decree dated July 12	 1967; 	(iii) in any case	 the decision in Miscellaneous Application No. 597/70 holding the decree to be a nullity operated as res judicata between the parties. The first objection was left open by all the Courts for future adjudication	 as the landlord denied the existence of any fresh agreement. The second and third objections alone were considered. In the judgment under appeal	 the High Court overruled them and hence this appeal by special leave and two other similar appeals. Dismissing the appeals the Court	 ^ HELD: 1. In Indu Bhushan Bose vs Rama Sundari and Anr.	 [1970 ] 1 S.C.R. 443	 the Supreme Court agreed with the view of the Calcutta and Rajasthan High Courts and held that the power of the State Legislature to legislate in respect of landlord and tenant of buildings was to be found not in Entry 18 of the List II	 but in Entries 6	 7 and 13 of List III of the Seventh Schedule to the Constitution and that such power was circumscribed by the exclusive power of Parliament to legislate on the same subject under Entry 3 of List I. But even before this decision Parliament took the view of the Calcutta Rajasthan High	 Courts as the correct view and proceeded to enact the Cantonment (Extension of Rent control Laws) Act	 1957	 by section 3 of which the Central Government was enabled	 by notification in the official Gazette to extend to any cantonment with such restrictions and modifications as it thought fit	 any enactment relating to the control of rent and regulation of house accommodation which was in force on the date of the notification in the State in which the Cantonment was situated. Though this Act came into force on December 18	 1957	 no notification was issued extending the provisions of the Bombay Rents Hotel and Lodging House Rates Control Act	 1947	 to Kirkee and other Cantonment areas within the State of Bombay until 1969. Apparently such a notification was thought unnecessary in view of the fact that the Bombay Act was supposed to operate within the said Cantonment areas because of the consistent view taken by the Bombay High Court regarding the applicability of the Bombay Act to such areas. In view of the Supreme Court decision in Indu Bhushan 's case	 it became necessary that a notification under section 3 of the Cantonment (Extension of Rent Control Laws) Act	 1957	 should be issued. It was accordingly done on December 29	 1969. But it was realised that the entire problem was not thereby solved since all such notifications as the one issued on December 29	 1969 could only be prospective and could not save decrees which had already been passed. Therefore	 Amending Act 22 of 1972 was enacted for the express purpose of saving decree which had already been passed. By section 2 of the Amending Act of 1972 the Principal Act of 1957 was itself deemed to have come into force on January 26	 1950. Original Section 3 was renumbered as subsection 1 and the words "on the date of the notification" were omitted and "were deemed always to have been omitted." [229 B G & 230 C D] 2. Under section 3 of the unamended Act	 1957	 a notification could be issued extending a State Legislation to a Cantonment area with effect from the date of notification. As a result of the introduction of sub section 2 of section 3 the notification can be given effect from an anterior date or a future late but it cannot be made effective from a date earlier than the commencement 226 of the State Legislation or the establishment of the Cantonment or the commencement of the Cantonment (Extension of Rent Control Laws) Act	 1957. Sub section 3 is merely consequential to sub section 2	 in that it provides that a State Legislation when extended to a Cantonment area with effect from the date of the notification from an anterior date	 such legislation is to stand extended with all the amendments to such State Legislation made after such anterior date but before the commencement of the 1972 Amending Act	 the amendments being applicable as and when they come into force. Sub section 4 makes provision for the saving of decrees or orders for the regulation of or for eviction from any house accommodation in a Cantonment made before the extension of the State Legislation to the Cantonment provided certain conditions are fulfilled. One condition is that the decree or order must have been made by any Court	 Tribunal or other authority in accordance with a law for the control of rent and regulation of house accommodation for the time being in force in the State in which such Cantonment is situated. In other words the decree or order must have been made by the wrong application of the State Legislation to the Cantonment area. If a decree or order has been made by such wrong application of the State Legislation to the Cantonment area it shall be deemed	 with enact from the date of the notification to have been properly made under the relevant provisions of the State Legislation. 1231 A H	 232 A BI 3. The applicability of sub section 4 cannot be confined to cases where notifications are issued with retrospective effect under sub section 2. Sub section 4 is not so confined. It applies to all cases of decrees or orders made before the extension of a State Legislation to a Cantonment area irrespective of the question whether such extension is retrospective or not. The essential condition to be fulfilled is that the decree or order must have been made as if the State Legislation was already in force	 although. strictly speaking	 it was not so in force. Subsection 4 is wide enough to save all decrees and orders made by the wrong application of State rent control and house accommodation legislation to a Cantonment area	 though such State Legislation could not in law have been applied to cantonment areas at the time of the passing of the decrees or order. The decree obtained by the respondent is saved by the pro visions of section 3	 sub section 4 of the Cantonment (Extension of Rent Control Laws) Act 22 of 1957	 as amended by Act 22 of 1972. [232 E F] 4. If the decision in the previous proceeding was to be regarded as res judicata it would assume the status of a special rule of law applicable to the parties relating to the jurisdiction of the Court in derogation of the rule declared by the legislature. [234 A] In the present case	 the executing Court had refused to exercise jurisdiction and to execute the decree on the ground that the decree was a nullity as the Bombay Rents	 Hotel and Lodging House Rates Control Act	 1947	 had no application to buildings in Cantonment areas. That defect having been re moved and all decrees obtained on the basis that the Bombay rent law applied to the Kirkee Cantonment area having been validated by Act 22 of 1972	 it cannot be said that the earlier decision holding that the decree was a nullity operated as res judicata. [234 B D] Mathura Prasad Bajoo Jaiswal and ors. vs Dessibai N. B. Jeejeebhoy	 (@) 836: followed.