The Independent Police Complaints Commission (IPCC) also announced it would request a second post-mortem test as part of an independent inquiry.I think we can assume that the autopsy will find bruising to Ian's legs (baton strike) and possible abrasions to his hands and knees (push to the floor). Of course there is the possibility that the shove and impact with the floor, or even the stress of the situation caused Ian's heart to give up.
What I do know is that the police officers involved should be suspended. And I do mean officers. An officer attacked Ian and the other officers did nothing. Who will police the police if they cannot police themselves. If you watch the video they don't even remonstrate with the attacking officer, so we must assume that they saw this assault as reasonable force. When I was in the Navy, if someone junior to you committed a crime and you did nothing to stop it, or failed to report it, then you were considered guilty of failing to do your duty. Those police officers who did nothing following this unprovoked attack on Ian Tomlinson are guilty of failing to do their duty.
I don't know if this unprovoked assault caused Ian's heart attack, but I do know that he was assaulted in a cowardly way. Ian was posing no threat to the public, the police or property. He was assaulted by a person who is paid to protect him.