New Delhi, Aug. 19 -- The Delhi Police on Tuesday defended its use of force against protesters during the July 20 student march, telling the Supreme Court that it resorted to a "graded" response only after the gathering ceased to be peaceful, with sections of the crowd breaching multiple layers of barricades and attempting to move towards Parliament. In a counter-affidavit, deputy commissioner of police (New Delhi) Sachin Sharma said that the allegation of excessive force was unsustainable given the scale of the gathering, claiming that about 5,000 police personnel were deployed to manage more than 30,000 protesters spread across nearly 3km. The ensuing confrontation left more than 240 police and other uniformed personnel, as well as around 200 protesters, injured. The affidavit has been filed in response to petitions seeking a court-monitored probe into alleged police excesses on July 20 and is intended to serve as a common response in four connected petitions. The matter is scheduled to come up before a Chief Justice of India-led bench on Tuesday. While police personnel initially attempted to regulate and contain the gathering, the situation deteriorated after protesters allegedly breached the barricades and moved towards Parliament, despite there being no permission for the march, the affidavit contends, adding that, as a result, the gathering consequently assumed the character of an unlawful assembly. The affidavit also said the march was a departure from the regulatory framework governing protests around Jantar Mantar and Central Vista. The Delhi Police's Standing Order provides for prior police permission for demonstrations at Jantar Mantar, caps the gathering at 1,000 persons, and prohibits marches from the designated protest site except a limited symbolic march with prior permission. On the allegation that police personnel used lathis fitted with nails, the affidavit said that examination of the available videos showed a solitary instance of such an object, but claims it was in the hands of a protester and not a police officer. The police further said it was not a police lathi, but a stick carrying the National Flag. It maintained that lathis form part of permissible crowd-control equipment and were used only to contain groups of protesters who had begun "attacking" personnel. The police alleged that videos also show groups of protesters targeting individual police officers, pulling off their protective gear, dragging them, and pushing them onto stone pavements. It claimed that 2,873 persons at the protest site had criminal cases registered against them, including allegations relating to murder, attempt to murder, dacoity, rape and offences under the Pocso Act. The police said their antecedents will be examined by the Special Investigation Team constituted by the Delhi Police commissioner. The police said that it would cooperate with any probe by a court-ordered committee into whether the force used was excessive On the use of facial-recognition technology at the protest site, the Delhi Police said the deployment is a "proportionate policing measure" and did not amount to indiscriminate surveillance of protesters....