You can call them back and ask for a copy, they may send it to you through mail, email or fax. Most likely you will need to submit a FOIA (Freedom of Information Act) request. Some agencies allow FOIA requests to be submitted online, if not then you can do it through mail or show up in person and fill out the form. Also, most police departments do not fulfill FOIA requests for active investigations so you will likely have to wait until the case is closed in court or until the police are finished with their part.