a freind of mine lives in a shared house and had a argument with one of the housemates.my mate was sweeping the floor and they started arguing the housemate confronted him and kept trying to snatch the broom away from him so eventually he let go in defence he kept putting his arms out pushing the housemate away trying to force the housemate away.he then left the house.now he recieved a letter from the police saying the room mate is pressing charges for abh as when he was puuting his arms out the housemate fell and has scratches now.
I Think... if you go to the police and ask them if you can make a counter claim in order that you will be asked to make a statement, the police will then have to take action by going to see him/her with notification of your intentions. they would then most likely point out the possibility of a stalemate situation (unless there were witnesses) they may advise the pair of you to drop it and to shake hands so to speak.
It would certainly be wise to seek advice though.... C. A. B. Perhaps?
Going strictly from what you've said, scratches alone would not amount to the offence of ABH. It would be Common Assault at best, and it would of course have to be proven.
I'm intrigued by this letter you say the Police sent your friend. It's not "normal" procedure. Have the Police by any chance asked your friend to attend the Station voluntarily?