Regardless of who did what first, your boyfriend can't press charges. Only the DA can do that. At most he can file a police report which will be received skeptically since it comes only after your boyfriend was arrested. Don't talk to the police, however, as it may expose your boyfriend to greater liability. Save the photos to share with your boyfriend's lawyer not the police.
If your boyfriend cannot afford a lawyer one will be appointed to represent him when he is arraigned.
He needs to get a lawyer now. Your lawyer will be able to guide you in what steps you need to take, get a lawyer now. Best Regards.
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