A division bench of Supreme Court held as follows in regards to the protection given to public servants from prosecution u/s 197 CrPC, mandating a sanction from Government.

8. The protection given under Section 197 Cr.P.C. is to protect responsible public servants against the institution of possibly vexatious criminal proceedings for offences alleged to have been committed by them while they are acting or adequate protection to public servants to ensure that they are not prosecuted for anything done by them, in the discharge of their official duties without reasonable cause, and if sanction is granted, to confer on the Government, if it chooses to exercise it, complete control of the prosecution. This protection has certain limits and is available only when the alleged act done by the public servant is reasonably connected with the discharge of his official duty and is not merely a cloak for doing the objectionable act. If in doing his official duty, he acted in excess of his duty, but there is a reasonable connection between the act and the performance of the official duty, the excess will not be a sufficient ground to deprive the public servant from the protection. The question is not as to the nature of the offence such as whether the alleged offence contained an element necessarily dependent upon the offender being a public servant, but whether it was committed by a public servant acting or purporting to act as such in the discharge of his official capacity. Before Section 197 Cr.P.C. can be invoked, it must be shown that the official concerned was accused of an offence alleged to have been committed by him while acting or purporting to act in the discharge of his official capacity. It is not the duty which requires examination so much as the act, because the official act can be performed both in the discharge of the official duty as well as in dereliction of it. The act must fall within the scope and range of the official duties of the public servant concerned. It is the quality of the act which is important and the protection of the section is available if the act falls within the scope and range of his official duty. There cannot be any universal rule to determine whether there is a reasonable connection between the act done and the official duty, nor is it possible to lay down any such rule. One safe and sure test in this regard would be to consider if the omission or neglect on the part of the public servant to commit the act complained of could have made him answerable for a charge of dereliction of his official duty: if the answer to this question is in the affirmative, it may be said that such act was committed by the public servant while acting in the discharge of his official duty and there was every connection with the act complained of and the official duty of the public servant. This aspect makes it clear that the concept of Section 197 Cr.P.C. does not get immediately attracted on institution of the complaint case.

Citations : [2008 RCR CRI 1 1042], [2008 AIR SC 1486], [2008 BLJR 56 1000], [2008 SCC 11 289], [2008 ALD CRI 2 134], [2008 SCALE 2 303], [2008 AICLR 2 150], [2008 MLJ CRI 2 458], [2008 AD SC 3 153], [2008 CCR 2 203], [2008 JT 2 374], [2008 CRIMES 1 346], [2008 SLT 3 680], [2008 AIOL 155], [2008 AIR SC 1375], [2008 BOMCR CRI SC 2 131], [2009 SCC CRI 1 130], [2008 SCR 2 580], [2008 SUPREME 1 572], [2008 AIC SC 63 28], [2008 CRLJ SC 2054], [2008 AIR SCW 1375]

Other Sources :

https://indiankanoon.org/doc/1809946/

https://www.casemine.com/judgement/in/5609ae6ee4b0149711413d79