Thank you for responding. Why don't you press charges?
Quite simply Its not up to you as a private citizen to "press charges"
I have heard the police ask if "you want to press charges" which is just a quick way of asking if you want him arrested, and the report / complaint will be sent to the DA to see if they will make the case, and pursue charges. Usually they do. They pick up the case, and its out of your hands, even though you may be required to testify. You have really no standing to bring any criminal charges against anyone.
Mostly if theres enough proof, police wont ask you anything. (black eye, broke jaw, dead) and offender will be arrested, charged, prosecuted, and whatnot, without you at all.
In the end, if your other hit you, you call the cops, you ask the report be report only, you cant go back a week later and ask he be arrested for it.