my 18yr old son and girlfriend were driving to her house and a guy started honking at them,(maybe everyone on the road, we are not sure), when they stopped at a red light, the guy got out of his truck and started yelling at my son, my son asked him "whats your problem?" the guy punched him in the eye, breaking his prescription eye glasses and putting a gash over his right eye. the guy then got in his vehicle and took off. my son got the description of the vehicle and the license plate number. the police said they probably couldnt do anything unless the guy admits to it?
Not sure how that is right, my son and his girlfriend can identify who did this,
That is absolutely not true. Assault cases are filed all the time based on a victim's word. The boy needs to go back to the police station and demand a report be taken. If the duty officer refuses, he needs to ask to speak to a sergeant. They can put together a photo line up of driver's license photos based on the registered owner of the car. Hopefully the boy can ID the assailant. I also hope he took pictures of his injuries.
I am also not sure why the police refused to take the report and forward it on to the local prosecutors office who really should be in charge of determining whether or not criminal charges would be filed. I might suggest you contact the local prosecutors office and tell them of the incident, giving them the name of the police department and police officer that you reported the incident to; and let them know that you do want to file criminal charges. You also have the option of filing a civil lawsuit against this person for battery.
Novel idea, arrest no one unless they admit to the crime--that would empty the jails pretty quickly. What you desribe is NOT correct--if your son was assaulted, he should demand the police take actioin.
Did your son tell you the police would not take the report? If so, its possible that for some other reason your son does not wish to press the matter. Chat with him before you attempt to push the matter with police.