Murari Mohan Dutt, J.:— This appeal is at the instance of the authorities of the commercial taxes and it is directed against the judgment of Sabyasachi Mukharji, J., whereby his Lordship made the rule nisi, which was obtained by the respondent Suresh Chandra Bose on his application under article 226 of the Constitution, absolute.

2. Bose is a qualified sanitary engineer and at the relevant time he had been working as a sanitary contractor. In 1950, Bose applied before the Commercial Tax Officer for being registered as a dealer under the Bengal Finance (Sales Tax) Act, 1941, under a mistaken impression that he was a dealer under the said Act and was liable to pay sales tax. Bose was registered as a dealer under the Act. He had submitted returns from 1951 to 1958 and paid a total sum of Rs. 18,812.45 on account of sales tax along with the returns. The case of the respondent was that the said sum was paid by him on a mistaken notion of the law. After the decision in Dukhineswar Sarkar and Brothers v. Commercial Tax Officer [1957] 8 S.T.C 478., and the decision of the Supreme Court in State Of Madras v. Gannon Dunkerley & Co., (Madras) Ltd [1958] 9 S.T.C 353 S.C., the law came to be well-settled that in the case of works contract there was no sale of goods and it was beyond the competence of the State Legislature to impose tax on the supply of materials used in such a contract. Accordingly, the respondent was not a dealer and rule 2(ii)(c) of the Bengal Sales Tax Rules, 1941, under which the respondent was assessed, was void and ultra vires. It was contended by the respondent that, in view of the said decisions, he became entitled to the refund of the amount of sales tax already paid by him and was entitled to have his registration certificate cancelled. The respondent submitted returns for the years 1959, 1960 and 1961 thereby declaring no sales or turnover. On 10th April, 1962, the respondent wrote a letter to the Commercial Tax Officer, Collootola Charge, stating, inter alia, that he was a sanitary contractor executing sanitary works. In the said letter, he requested the Commercial Tax Officer to cancel his registration as a dealer in view of the decisions of the Supreme Court in the Dukhineswar Sarkar's case and the Gannon Dunkerley's case, referred to above. In reply to the said letter, the Commercial Tax Officer by his letter dated 26th May, 1962, informed the respondent that the question of cancellation of his registration certificate would be considered on completion of the pending assessment. The respondent, therefore made a further representation to the Commercial Tax Officer by his letter dated 7th June, 1962, regarding the cancellation of his registration certificate. He also stated that, in view of the fact that rule 2(ii)(c) of the Bengal Sales Tax Rules, 1941, had been declared ultra vires by the Supreme Court, the Commercial Tax Officer was acting in excess of or without jurisdiction in proceeding to assess the respondent under the Act. The Commercial Tax Officer, however, did not take any action in the matter, but issued a notice in form VIIA under rule 55A of the Bengal Sales Tax Rules calling upon the respondent to show cause why penalty should not be imposed upon him for non-payment of arrears of tax for the years 1955, 1956 and 1957 ending on the 31st March of each year. On 15th June, 1962, the respondent submitted an application before the Commercial Tax Officer stating that the assessments were made under rule 2(ii)(c) of the Bengal Sales Tax Rules, 1941, which was ultra vires and, as such, the assessments were without jurisdiction. He requested the Commercial Tax Officer to withdraw the said notices. The Commercial Tax Officer, however, did not accede to the request made by the respondent. The respondent moved an application under article 226 of the Constitution and obtained a rule nisi being C.R No. 388(W) of 1962. The said rule was discharged by a learned single Judge of this Court, but, on appeal before the Division Bench, it succeeded. The appeal court observed, inter alia, as follows:

“rule 2(ii)(c) of the Rules framed under the Act having been declared to be ultra vires, the tax imposed on the appellant under the assessment orders for the years mentioned above cannot be sustained. Secondly, if the imposition of tax itself was invalid, no proceedings can be taken against the appellant for imposing a penalty upon him for default in payment of the tax.”

3. It was the case of the respondent that, after the said decision of the appeal court, he was advised that the assessments, having been made on the basis that the respondent was a dealer and not a contractor, were all invalid and the money paid by the respondent in respect of the said assessments became refundable to him. Accordingly, the respondent wrote to the Secretary, Department of Finance, West Bengal, Calcutta, on 2nd May, 1972, claiming refund of the said sum of Rs. 18,812.45. The respondent did not receive any reply to the said letter. On the contrary, steps were taken for realisation of the dues on the basis of the assessments for the years 1963, 1964 and 1965 and certificate proceedings were started against the respondent. Thereafter, the respondent made an application for cancellation of the registration certificate which was cancelled by the Commercial Tax Officer with effect from 22nd August, 1972. On 1st September, 1972, the respondent made seven sets of applications before the Commercial Tax Officer, Collootola Charge, claiming refund of diverse amounts of taxes realised illegally and/or without any authority of law from, him for the years 1951-52 to 1957-58. All the said applications for refund were rejected by the Commercial Tax Officer which will appear from his letters received by the respondent on 12th January, 1973, on the ground that no excess payment had been made by the respondent during the periods in question. Thereafter, the respondent moved a writ petition before this Court and obtained a rule nisi out of which this appeal arises. In the writ petition, the respondent challenged the failure of the appellants to refund to him the sum of Rs. 26,798.01. The respondent also prayed for a direction restraining the appellants from proceeding with the certificate cases started against him for the realisation of the said amount. The learned Judge, as stated already, made the rule nisi absolute directing refund to the respondent the sums of money which the respondent had paid for the various years for which due evidence would be produced by the respondent before the Commercial Tax Officer. Further, the learned Judge restrained the appellants from enforcing the certificate cases started against the respondent. The principal question that is involved in this appeal is whether the respondent is entitled to the refund of the amount of tax paid by him, being the sum of Rs. 26,798.01, for the years from 1951 to 1958. It is apparent that, after the above decisions of the Supreme Court, the Commercial Tax Officer had no authority and jurisdiction to realise sales tax from the respondent, for the rule, being rule 2(ii)(c) of the Bengal Sales Tax Rules, was ultra vires. The respondent, therefore, was not a dealer within the meaning of the Bengal Finance (Sales Tax) Act, 1941. It was due to a mistaken notion of law before the said rule was declared ultra vires that the respondent applied for being registered as a dealer. The Commercial Tax Officer also in his turn was under the same mistake in treating the respondent as a dealer and assessing him as such for the impugned periods of assessment. The mistake was, therefore, common to both the respondent and the Commercial Tax Officer. As soon as the respondent came to know of that mistake committed by him, he pointed out the same to the Commercial Tax Officer by his letter dated 10th April, 1962, requesting him to cancel his registration as a dealer. The above two Supreme Court cases were also referred to in the said letter. Thereafter, he also made subsequent representations to the Commercial Tax Officer, but, instead of granting any relief to the respondent as prayed by him, the Commercial Tax Officer proceeded to impose penalty on the respondent for his non-payment of the arrears of sales tax for the subsequent periods. The penalty that was imposed was set aside by this Court on the ground that the Commercial Tax Officer had no authority or jurisdiction to realise sales tax from the respondent as the said rule 2(ii)(c) was ultra vires the power of the State Legislature.

4. It is, however, contended by Mr. Dutta, the learned Advocate appearing on behalf of the appellants, that the orders of assessments for the periods in question, that is, for the years from 1951 to 1958, not having been challenged by the respondent in appeal, the said orders became final and cannot be reopened for the purpose of refund to the respondent. In support of this contention, reliance has been placed on behalf of the appellants on the decision of the Privy Council in Commissioner of Income-tax, West Punjab v. Tribune Trust, Lahore. In that case, the assessee, the Tribune Trust, claimed that, as the income of the trust derived from property held under trust wholly for charitable purposes, it was exempted from tax under section 4(3)(i) of the Indian Income-tax Act, 1922. It was held by the Privy Council that the assessments were not nullity, but they were Valid and effective until they were set aside: It was further observed that the only remedies open to the taxpayer, whether in regard to appeal against assessment or to claim for refund, were to be found within the four corners of the Income-tax Act, and that the assessee had no right enforceable against the Commissioner of income-tax to require refund of tax by it upon grounds of equity and good conscience. Raja Jagdambika Pratap Narain Singh v. Central Board of Direct Taxes was also a case of refund. In that case, the appellant had claimed the income derived by him from fruits and fallen trees of mango grove to be agricultural income not assessable under the Income-tax Act, 1922. Ultimately, in 1963, the High Court on a reference held such income to be an agricultural income. In the meantime, the assessments were similarly made for the assessment years 1940-41 to 1961-62, but the appellant allowed the assessments for most of those years to become final and preferred appeals for certain years to the Appellate Assistant Commissioner and did not take the matter any further. After the judgment of the Supreme Court in the reference for 1939-40, the appellant applied to the Central Board for refund of tax for the years 1940-41 to 1961-62, but the Board declined. Thereafter, the appellant filed a writ petition in September, 1968, in the High Court, and the High Court dismissed the petition on two grounds: (a) that the assessment orders had become final, the appellant not having taken advantage of his statutory remedies, and (b) that several years had elapsed between the order for the assessment year 1961-62 and even the judgment of the High Court in 1963 and the writ petition. The Supreme Court in dismissing the appeal has, however, inter alia, observed that mere exemptions from taxation of income otherwise competently taxable fell wholly within the jurisdiction of the officer for determination. There is a fundamental difference where the claim is that agricultural income is beyond the legislative competence of Parliament to enact and altogether outside the jurisdiction of the Income-tax Officer. It may well be contended that the impost is ultra vires his powers and, therefore, a nullity. Merely because an order has been passed by the officer and has not been appealed against, it does not become legal and final, if otherwise it is void; for instance, if there is a flagrant violation of natural justice, the order by a Tribunal may be a nullity.

5. On the strength of the above two decisions, it has been strongly urged on behalf of the appellants that as the respondent had not taken any steps for getting the orders of the Commercial Tax Officer set aside by preferring appeals the same became final and conclusive and no refund could be made. We regret; we are unable to accept the contention. In these two cases, the appellant claimed exemption from payment of tax. It was not the case of the appellants in either of the said cases that the imposition of tax was ultra vires and beyond the competence of the legislature. There is a distinction between exemption claimed on a particular item and the provision of law under which assessments are made is ultra vires. In the first case, the order of assessment is not void but illegal and liable to be set aside in appeal, but, in the other case, the assessment is void. A void assessment, in our opinion, is not required to be set aside and it does not attain finality at any stage. The Supreme Court itself has observed in the Raja Jagdambika's case that if the impost is ultra vires the powers of the Income-tax Officer and, therefore, a nullity, merely because the order has been passed by the officer and has not been appealed against, it does not become legal and final if otherwise it is void. In the instant case also, there could be no doubt that the assessments were void as the respondent was not a dealer at all and so the assessments had not become legal and conclusive by lapse of time. The above decisions are, therefore, of no help to the appellants.

6. The next point that has been urged on behalf of the appellants is the bar of limitation to the claim for refund made by the respondent. It is argued that the refund has to be claimed within a certain time and if such claim is made beyond the time, it will not be maintainable. Section 12(1) of the Bengal Finance (Sales Tax) Act, 1941, provides as follows:

“The Commissioner shall, in the prescribed manner, refund to a dealer applying in this behalf any amount of tax or penalty paid by such dealer in excess of the amount due from him under this Act, either by cash payment or, at the option of the dealer, by deduction of such excess from the amount of tax due in respect of other period:

Provided that no refund shall be made unless the claim for refund is made within twelve months from the date of the assessment of tax or the date of the imposition of penalty or within six months from the date of any final order passed on appeal, revision or review under section 20 or reference under section 21, whichever period expires later.”

7. Relying on the proviso to section 12(1), it has been urged on behalf of the appellants that as the respondent has not made any application for refund within twelve months from the respective dates of assessments, such claim for refund is barred by limitation. Section 12(1) applies to the case of the refund of the tax or penalty paid by a dealer in excess of the amount due from him under the Act. Section 12(1), therefore, contemplates that the person claiming a refund is a dealer within the meaning of the Act, and that such a dealer has made payment of tax or penalty in excess of the amount that was assessed or due from him. In the instant case, the first condition of section 12(1) is not satisfied, namely, that the respondent was not a dealer at all. Accordingly, in our view, section 12(1) and, consequently, the proviso to the same, are not at all applicable. This contention of the appellants, therefore, fails.

8. It is next contended on behalf of the appellants that even assuming that section 12(1) does not apply, still the respondent should have made the claim within a reasonable time. The decision of the Supreme Court in the Gannon Dunkerley's case was given in 1958. It is contended that the respondent having come to know of the legal position in 1962 that the taxes were illegally realised from him for the impugned periods, he should have made the application at least within three years from his knowledge. The respondent, however, made the application for refund on 29th August, 1972, and, as such, the application for refund was barred by limitation. There is no period of limitation fixed under the law for claiming refund of tax realised by virtue of an order of assessment, which is void. However, the Supreme Court has in some cases laid down that a claim for refund should be made within a reasonable period. In Burmah Construction Co. v. State of Orissa, the appellant claimed refund of tax paid by it although no tax was payable by it as a building contractor. His claim for refund was rejected by the sales tax authorities on the ground that such claim was made beyond the period of twenty-four months as prescribed in the proviso to section 14 of the Orissa Sales Tax Act, 1947. Section 14 including the proviso thereto is somewhat similar to Section 12(1) of the Bengal Finance (Sales Tax) Act, 1941, and its proviso except that under the proviso to section 14 of the Orissa Sales Tax Act, the period within which the claim for refund is to be made is twenty-four months. It was contended on behalf of the appellant before the Supreme Court that section 14 was ultra vires the power of the State Legislature. That contention was overruled by the Supreme Court and the Supreme Court directed that the State of Orissa should refund to the appellant that part of the sales tax which had been paid by it if the order of assessment pursuant to which payment was made was twenty-four months of the date on which the writ petition was filed before the High Court. This decision is mainly concerned with the question whether section 14 of the Orissa Sales Tax Act was ultra vires the State Legislature or not.

9. In State of Madhya Pradesh v. Bhailal Bhai, it has been observed by the Supreme Court that where a person comes to the court for a relief under article 226 of the Constitution on the allegation that he has been assessed to tax under a void legislation and having paid it under a mistake is entitled to get it back, the court, if it finds that the assessment was void, being made under a void provision of law, and the payment was made by mistake, is still not bound to exercise its discretion directing repayment. Whether repayment should be ordered in the exercise of this discretion will depend in each case on its own facts and circumstances. It is not easy nor is it desirable to lay down any rule for universal application. As a general rule, it may be stated, if there has been unreasonable delay, the court ought not ordinarily to lend its aid to a party by this extraordinary remedy of mandamus. Again, where, even if there is no such delay, the Government or the statutory authority against whom the consequential relief is prayed for raises a prima facie triable issue as regards the availability of such relief on the merits on the grounds like limitation, the court should ordinarily refuse to issue the writ of mandamus for such payment. It has been further observed that the maximum period fixed by the legislature as the time within which the relief by a suit in a civil court must be brought may ordinarily be taken to be a reasonable standard by which delay in seeking remedy under article 226 can be measured. The court may consider the delay unreasonable even if it is less than the period of limitation prescribed for a civil action for the remedy, but where the delay is more than this period, “it will almost always be proper for the court to hold that it is unreasonable”.

10. In State Of Kerala v. Aluminium Industries Ltd., Kundara, Quilon., it has been observed by the Supreme Court that money paid under a mistake of law comes within the word “mistake” in section 72 of the Contract Act and there is no question of estoppel when the mistake of law is common to both the assessee and the taxing authority. If refund is not made, remedy through court is open, subject to the same restriction and also to the bar of limitation under article 96 of the Limitation Act, 1908, namely, three years from the date when the mistake becomes known to the person who has made the payment by mistake. Further, it has been observed that it is the duty of the State to investigate the facts when the mistake is brought to its notice and to make a refund if the mistake is proved and the claim is made within the period.

11. Relying on the above decisions, it has been urged on behalf of the appellants that as the application for refund was made by the respondent long after three years of the detection of the mistake by him, the application was barred by limitation. Much emphasis has been laid by the learned Advocate appearing on behalf of the appellants on the observation of the Supreme Court in the Bhailal Bhai's case to the effect that where the delay is more than the period of limitation prescribed for a civil action, which is three years, “it will almost always be proper for the court to hold that the delay is unreasonable”. At the same time, in that case, the Supreme Court has also observed that it is not easy nor is it desirable to lay down any rule for universal application, and that as a general rule it may be stated that whether repayment should be ordered in the exercise of the discretion of the High Court under article 226 of the Constitution will depend in each case on its own facts and circumstances. In our view, in the Bhailal Bhai's case, the Supreme Court has not laid down any fixed period, namely, three years, when the mistake was detected as in article 96 of the Indian Limitation Act, 1908. As we have understood the decision of the Supreme Court in the Bhailal Bhai's case, it has been laid down by the Supreme Court that the High Court should not normally exercise its discretion when the claim for refund is made beyond the period of three years from the date the mistake came to be known to the party. The use of the words “almost always” is very significant. The facts and circumstances of a particular case may be such as to persuade the High Court to exercise its discretion in favour of the party claiming refund even beyond the period of three years from the date of his knowledge of the mistake. If a party, after coming to know of the mistake committed by him in paying taxes not payable by him because the law under which the taxes were realised was void, does not take any step in the matter either by making an application for refund or bringing it to the notice of the authorities concerned about the illegal realisation of the tax under a common mistake of law or, in other words, if the party sits idle during the period of time within which a civil action is to be brought, in such a case, the High Court should not exercise its discretion in granting relief to that party for refund. The remedy provided by article 226 of the Constitution is not meant for a careless and negligent person. Before any relief is granted to a person, the court should be satisfied that he was diligent all through and did not waste time before he came for relief under article 226.

12. We may now consider whether the respondent can be said to be so negligent as to refuse him the relief prayed for by him for the refund of taxes illegally realised from him under the void provision of law. It has been stated already that as soon as it came to his knowledge that the taxes paid by him were illegally realised by the appellants under a void rule, namely, rule 2(ii)(c) of the Bengal Sales Tax Rules, he brought that fact to the notice of the Commercial Tax Officer by his letter dated 10th April, 1962. By that letter, he requested the Commercial Tax Officer to cancel his registration as a dealer in view of the decisions in the Dukhineswar's case and the Gannon Dunkerley's case. It was the duty of the State to refund the taxes realised from the respondent illegally. There cannot be any doubt about that duty of the State, which has also been noticed by the Supreme Court in State Of Kerala v. Aluminium Industries Ltd., Kundara, Quilon. [1965] 16 S.T.C 689 S.C. Instead of refunding the amount of tax to the respondent, the Commercial Tax Officer passed orders imposing penalty on the respondent for non-payment of arrears of tax which, as stated already, this Court had set aside. It thus appears that since the very date of his knowledge about the mistake of law that was committed by him, the respondent had been making representations to the appellants, but in vain. After the order imposing penalty on the respondent was set aside by this Court, he made an application for refund. Thus, it appears that the State Government did not perform its duty by refunding the amount of tax to the respondent, instead they did not pay any heed to the representation of the respondent. In our view, it would be doing injustice to the respondent, if we allow the appellants to take advantage of their own wrong. The respondent, in our opinion, cannot be said to be negligent in the matter of refund of tax. For the reasons' aforesaid, we are of the view that the bar of limitation of three years as relied on by the appellants is not applicable to the facts and circumstances of this case. No other point has been urged in this appeal.

13. In these circumstances, the appeal is dismissed, but in view of the facts and circumstances of the case, there will be no order for costs.

14. Leave for appeal to the Supreme Court has been prayed for by the learned Advocate appearing on behalf of the appellants. The prayer is disallowed.

15. The operation of this judgment will remain stayed till three weeks after the long vacation.

Ram Krishna Sharma, J.:— I agree.

16. Appeal dismissed.

17. Leave to appeal disallowed.