Every case worker has a supervisor. Every supervisor has a boss. Police Reports are a matter of public record. Writing down all of the events preceding, during, and after the event as well as you can recall each five second interval is helpful. Past criminal or civil conduct leading to arrests and/or restraining orders and protective orders involving your mother in law and/or her husband might also be helpful. Collect up all of the information that you can with names and contact phone numbers and addresses and then go see a lawyer so that the lawyer can look at the information and advise you properly.