ORDER : Heard Sri N. Bhujanaga Rao, learned Deputy Solicitor General of India appearing for the petitioners and Sri K. Vivek Reddy, learned Senior Counsel on behalf of Sri G. Bheema Chary for the respondents and perused the record. 2. W.P.No.9758 of 2021, is filed under Article 226 of the Constitution of India, with the following prayer viz., the petitioners prays the Hon'ble Court to issue Writ, order or direction, especially one in the nature of Writ of Certiorari, calling for the records relating to order dated 24/1/2020 in O.A.No.372 of 2018 on the file of the Hon'ble Central Administrative Tribunal, Hyderabad Bench, Hyderabad and quash the same by declaring illegal, arbitrary, contrary to law and pass such other order or further orders as deem fit and proper. 3. The present Writ Petition has been filed by the Union of India, represented by its Secretary, Department of Personnel and Training (DoPT) challenging the order dated 24.01.2020 of the Central Administrative Tribunal (hereafter “Tribunal” for brevity) in O.A.No.21/372/2018 (hereafter “O.A” for brevity). Factual matrix 4. The core facts leading to the filing of the present writ petition are as follows: i. The respondent No.1 is an All India Services Officer belonging to the Indian Police Service (IPS) borne on the Tamil Nadu cadre. ii. The respondent No.1 was allowed Inter-Cadre Deputation from the State of Tamil Nadu to erstwhile cadre of Andhra Pradesh State for a period of five (05) years vide Ministry of Home Affairs order No.I-21021/07/2010-IPS.IV dated 21.10.2010. iii. Respondent No.1 joined the erstwhile cadre of Andhra Pradesh on 14.01.2011. Accordingly, the respondent No.1’s approved period of Inter-Cadre Deputation of five years ended on 13.01.2016. iv. The respondent No.1 continued to serve in the state of Andhra Pradesh beyond the sanctioned tenure of five years. The over stay of the respondent No.1 was purportedly due to the administrative difficulties and service exigencies faced by the newly bifurcated State of Telangana, which had a deficit of senior All India Service officers. v. The Ministry of Home Affairs initially brought it to the notice of the Tamil Nadu Government by letter dated 04.05.2016 that the respondent No.1 had not reported to her parent cadre after expiry of the approved period of Inter Cadre Deputation. vi. The Ministry also directed the State of Telangana by letter dated 28.06.2016 to relieve the respondent No.1 if not already relieved. vii. vi. The Ministry also directed the State of Telangana by letter dated 28.06.2016 to relieve the respondent No.1 if not already relieved. vii. The respondent No.1 was finally relieved from Telangana on 20.05.2017. viii. The Ministry of Home Affairs by Memo dated 17.01.2018 treated the period of over stay of the respondent No.1 i.e., from 14.01.2016 till 19.05.2017 as unauthorized over stay, that “the period of over stay shall not be counted for any increment with cumulative effect”; directing the recovery of excess payment and stating that adverse notice would be taken against her during empanelment. ix. The respondent No.1 challenged Memo dated 17.01.2018 before the Tribunal by following O.A. The Tribunal allowed the O.A by order dated 24.01.2020 and set aside the Memo dated 17.01.2018 declaring it arbitrary, illegal and contrary to service conditions. The Union of India (Petitioners) filed the present writ petition challenging the said order of the Tribunal. Submissions of the petitioners 5. Learned Deputy Solicitor General appearing on behalf of the petitioners, advanced the following submissions hereunder: i. That the service conditions of All India Service officers, including matters relating to inter-cadre deputation, are comprehensively governed by the All-India Services (Cadre) Rules, 1954. In particular, Rule 6(1) vests exclusive authority in the Central Government as the Cadre Controlling Authority to regulate Inter- cadre movement and postings, and no State Government can act contrary thereto. ii. That Inter-cadre deputation being an exception to the normal rule of service in the parent cadre, any extension beyond the sanctioned period can only be granted with the prior and prospective approval of the Central Government. The unilateral retention of respondent No.1 by the borrowing State, even on the ground of administrative exigencies is without legal sanction, non est in law, and incapable of either binding the Central Government or conferring any enforceable right upon the respondent No.1. iii. That the retention of respondent No.1 in the State of Telangana, though appears to be pursuant to a proposal of the State of Telangana dated 27.09.2016 for extension of her tenure while on Inter-cadre deputation, was not actually the result of a suo motu decision of the Government of Telangana. Rather, the proposal was initiated at the instance of respondent No.1, who made a representation to the Director General of Police, Telangana, asserting that the respondent No.1 was eligible to be considered for extension beyond five (05) years. iv. Rather, the proposal was initiated at the instance of respondent No.1, who made a representation to the Director General of Police, Telangana, asserting that the respondent No.1 was eligible to be considered for extension beyond five (05) years. iv. That the Memorandum dated 17.01.2018 does not partake the character of a disciplinary or punitive order. It merely records the administrative and regulatory consequences flowing from non- compliance with the statutory Cadre Rules. In issuing the said memorandum, the Central Government acted strictly within its jurisdiction as the Cadre Controlling Authority, in determining the manner in which the period of unauthorised overstay is to be treated. v. That the CAT committed an error of law and Jurisdiction by substituting its own assessment, in place of the decision taken by the competent authority, which amounts to judicial overreach into matters of cadre control and service policy, which lie within the exclusive domain of the executive under the statutory framework governing All India Services. Submissions of the respondent No.1 6. Learned Senior Counsel appearing on behalf of the respondent No.1, advanced the following submissions hereunder: i. That the respondent No.1 continued to discharge her duties strictly in compliance with the explicit directions issued by the Government of Telangana. The respondent No.1 has no discretion to unilaterally relinquish charge or report back to the parent cadre, as such conduct would have amounted to abandonment of duty and invited disciplinary action. ii. That the delay in reliving her was solely due to State’s own administrative decisions and not to any lapse, request, or omission on her part, however, the State Government in its affidavit filed before the Tribunal has confirmed that the respondent No.1’s continuation was entirely at the request and instance of the State Government. iii. That the continuation of respondent No.1 beyond the sanctioned deputation period was compelled by post-bifurcation administrative exigencies and shortage of senior officers, and that penal consequences for such overstay are arbitrary, disproportionate, and violative of Article 14 of the Constitution. iv. That respondent No.1 rendered full and effective service during the relevant period and, having accepted such service and paid salary, denial of consequential benefits would be inequitable and contrary to the doctrine of quantum meruit. 7. We have taken note of the respective contentions urged. Analysis and finding 8. iv. That respondent No.1 rendered full and effective service during the relevant period and, having accepted such service and paid salary, denial of consequential benefits would be inequitable and contrary to the doctrine of quantum meruit. 7. We have taken note of the respective contentions urged. Analysis and finding 8. In the present case, the retention of respondent No. 1, though purportedly based on the proposal dated 27.09.2016 for extension of her tenure on inter-cadre deputation, was not initiated suo motu by the Government of Telangana. The record shows that respondent No. 1 made a representation to the Director General of Police, Telangana, claiming eligibility for extension beyond five (05) years on the basis of DoP&T O.M.No.140117/2/2016-AIS-II dated 27.06.2016. Acting on this representation, the proposal was recommended by the Director General of Police and thereafter forwarded by the State Government to the Central Government citing shortage of officers. On examination of the said Office Memorandum, this Court finds that such reliance was misplaced and that the proposal did not stem from any independent or suo motu decision of the State Government. 9. This Court also finds that the period of overstay of respondent No.1, having occurred de hors the statutory sanction of the Central Government, is in law an unauthorised period of absence from the parent cadre. The administrative exigencies of the borrowing State cannot unilaterally dilute or override the Central Rules. Any such interpretation would fundamentally undermine the unified structure of the All-India Services, effectively converting a deputed officer into a permanent asset of the borrowing State without the approval of the Cadre Controlling Authority. 10. The reliance placed by the learned Senior Counsel in Central Council for Research in Ayurvedic Sciences v. Bikartan Das, (2023) 16 SCC 462 fails to support respondent No.1’s contention and, does not advance her case inasmuch as the order of the Tribunal suffers from error of law and Jurisdiction. 11. At the outset, this Court finds that the Tribunal failed to uphold the absolute supremacy of the statutory framework governing Inter- cadre deputation under the All-India Services (Cadre) Rules, 1954. Rule 6(1) makes it unequivocally clear that the power to 'depute' and, by necessary implication, the power to sanction the tenure of that deputation, rests exclusively with the Central Government. The relevant Rule is extracted hereunder for ready reference: 6. Rule 6(1) makes it unequivocally clear that the power to 'depute' and, by necessary implication, the power to sanction the tenure of that deputation, rests exclusively with the Central Government. The relevant Rule is extracted hereunder for ready reference: 6. Deputation of cadre officers – (1) A cadre officer may, with the concurrence of the State Governments concerned and the Central Government, be deputed for service under the Central Government or another State Government or under a company, association or body of individuals, whether incorporated or not, which is wholly or substantially owned or controlled by the Central Government or by another State Government. Provided that in case of any disagreement, the matter shall be decided by the Central Government and the State Government or State Governments concerned shall give effect to the decision of the Central Government. 12. It is pertinent to note that the Tribunal committed a jurisdictional error in treating the Memorandum issued by the Ministry of Home Affairs as a disciplinary penalty. A disciplinary penalty necessarily pre- supposes a formal inquiry into alleged misconduct, such as wilful absence or disobedience of orders. The impugned Memorandum, however, represents a regulatory consequence flowing from a particular status, namely unauthorised retention, and not from any adjudication of fault or misconduct. The Central Government, having sanctioned deputation for a specified period, is required to account for any period of overstay in accordance with its extant policy so as to preserve the integrity of the cadre roster and the all-India seniority structure. Treating such period as unauthorised absence or as leave without pay is thus a natural, logical, and non-punitive administrative consequence arising from the failure of the borrowing State and respondent No.1 to adhere to the Central Government’s deputation orders. 13. The contention of respondent No. 1 that executive instructions cannot be applied retrospectively, based on reliance on Sonia v. Oriental Insurance, (2007) 10 SCC 627 is misplaced, and does not advance the case of respondent No.1, as there is no retrospective application of the executive instructions in the present case. 14. With regard to the submission that respondent No.1 continued to discharge duties during the relevant period, it is well settled that considerations of equity cannot override mandatory statutory rules. 14. With regard to the submission that respondent No.1 continued to discharge duties during the relevant period, it is well settled that considerations of equity cannot override mandatory statutory rules. The Hon’ble Supreme Court in Raghunath Raj Bareja and others v. Punjab National Bank and others, MANU/SC/5456/2006 = 2007 (4) ALT 4 (SC) has repeatedly cautioned that equity cannot supplant the law. Both the borrowing State and respondent No.1 were fully aware of the All-India Service Rules governing inter-cadre deputation. The borrowing State was obliged to relieve respondent No.1 upon expiry of the sanctioned tenure, and respondent No.1, being a senior All-India service officer, was equally obligated to ensure compliance with the orders of the Central Government and to report any delay to the Ministry of Home Affairs. The failure to do so, even if not wilful, necessarily attracts the administrative consequences imposed by the Cadre Controlling Authority in order to uphold the rule of law. 15. For the foregoing reasons, this Court is of the considered view that the Tribunal has acted beyond scope of its limited judicial review jurisdiction and rendered a decision contrary to the statutory scheme. 16. Accordingly, the Writ Petition is allowed, setting aside the order dated 24.01.2020 passed in O.A.No.372 of 2018. The memorandum dated 17.01.2018 is hereby restored. No costs. As a sequel, miscellaneous petitions, pending if any, stand closed. No costs.