To prepare for the hearing, a petitioner should gather evidence, like photographs, medical reports, police reports, and text messages. Also, the petitioner can contact witnesses and ask them to come testify. Witnesses can be people involved in the situation, like the petitioner. Witnesses can also be other people who have direct information about the case, like police officers . Witnesses should be people who saw what happened with their own eyes or heard it happen with their own ears. If you need you need a person to testify as a witness but that person says they will not come to court, you may need a “subpoena.” A subpoena is a written command by the court that the person with the papers or pictures must give them to you.