Hire a criminal defense attorney as soon as you possibly can. If you cannot afford one, the court will appoint one for you.
And stay away from alcohol parties with kids. What are you thinking? Also, stop playing lawyer with the police. Lawyer's are lawyers. Kids aren't lawyers. If the police seized evidence in violation of the law, an attorney can fix that. The police have TREMENDOUS power to keep the peace in the moment, and that includes cuffing loud-mouths. Don't be that guy.