New Delhi: The Supreme Court on Monday said it will lay down a "comprehensive protocol" on the use of pellet guns against protestors."We would like to lay down a complete protocol on how and when it can be used," a three-member bench headed by Chief Justice of India (CJI) Surya Kant verbally remarked.Also Read: Amit Shah must explain in Parliament lathicharge-pellet gun action on students: KhargeIn a related development, the bench clarified that Delhi and other state governments are at liberty to withdraw FIRs against protestors involved in the recent student protests in Delhi's Jantar Mantar and various other states.The bench clarified its order last month which said that the police can continue prosecution of protestors with criminal antecedents. The bench clarified that "criminal antecedents" is to be read as "grave and heinous offences".The direction came after the counsel for some protestors told the bench that the words "criminal antecedents" in the earlier order were being used to keep cases pending even when such antecedents were for minor issues like driving offences or some earlier protests.In its July 28 order, the bench observed that the allegations of police excesses against participants at the recent student protest "prima facie made out a case for an independent probe".Also Read: Supreme Court permits pellet guns in exceptional cases during Jantar Mantar protest hearingThere is no doubt that there "should be an independent, fair, speedy and thorough probe," said a three-member bench headed by Chief Justice of India Surya Kant. The bench is of the prima facie view to constitute a "high-powered investigation committee" to look into the alleged police excesses and violence in Delhi and other states, CJI Kant had said on July 28.However, the Bench had granted the Union government and Delhi Police an opportunity to place their version on record. It said other states where the violence took place may also place their version on record.Accordingly, it had issued notice to the chief secretaries of Delhi, Maharashtra, Bihar, Kerala, Madhya Pradesh and Uttar Pradesh.On Monday, the bench said it was contemplating the formation of a special investigation team of police officers to investigate the allegations of police excesses or a committee headed by a retired judge."There are two things in our mind: One is an SIT of police officers to investigate or to have a committee headed by a retired judge," the bench remarked. The court eventually decided to wait for responses from various states before passing any order. The case will come up for resumed hearing on August 18.