Section 271

When a peace officer or police officer is proceeding lawfully to arrest, with or without warrant, a person for an offence which is a felony, and is such that the offender may be arrested without warrant, and the person sought to be arrested takes to flight in order to avoid arrest, it is lawful for the peace officer or police officer and for any person lawfully assisting him, to use such force as may be reasonably necessary to prevent the escape of the person sought to be arrested, and, if the offence is such that the offender may be punished with death or with imprisonment for seven years or more, may kill him if he cannot by any means otherwise be arrested.