He is looking at a strike, potential prison... You need a good criminal defense attorney. I'd strongly suggest you find someone who focuses on criminal law and who routinely practices in the court where this case will be heard.
The above answer is for general information only and is based on the information you posted. Every case is fact dependent, so to get a thorough analysis of your situation, you will need to consult face to face with an attorney licensed to practice in the jurisdiction where the incident took place. Do not conclusively rely on any information posted online when deciding what to do about your case.
He needs an attorney immediately. Many reputable attorneys offer a free consultation. Start calling those in your area. Good luck.
The response above is not intended as legal advice since it’s impracticable to provide thorough, accurate advice based upon the query without additional details. It is highly recommended that one should seek advice from a criminal defense attorney licensed in your jurisdiction by setting up a confidential meeting. Moreover, this response does not constitute the creation of an attorney-client relationship since this message is not a confidential communication because it was posted on a public website, thereby publicly disclosing the information, which is another reason to setup a confidential meeting with an attorney.
Your boyfriend needs a criminal defense attorney -- MONDAY!!
In no way am I offering you legal advice, and in no way has my comment created an attorney-client relationship. You are not to rely upon my note above in any way, but insted need to sit down with counsel and share all relevant facts before receiving fully-informed legal advice. If you want to be completely sure of your rights, you must sit down with an experienced criminal defense attorney to be fully aware of your rights.
That is a very serious crime and he could do prison time if convicted. What he needs to do is not talk about it with anyone except his attorney. If he is in jail, when you speak with him, the phone will be monitored and anything you talk about will be provided to the police and the district attorney. So if he says anything about the case, it will be used against him. Tell him this and then talk about anything but the facts of the case. But he needs legal representation right away.