Basically A has locked B in a hall and has cut off the power supply. B is locked in for an hour or so and is in astate of panic and hurriedly tries to find for the exit. Later on after half an hour A comes to open the door B hit A on the head and runs away. A dies. The CCTV records show A coming, then B coming and then B leaving.
How to prove that the whole act was a mischief played by A and not a murder by B as the CCTV shows. Is there any law or any exception in any law that can negate the CCTV footage as, as it is it is not showing what truely happened.