Write a general trial script that includes the main purposes of each witness and whether each witness is for the prosecution or the defense. Keep the trial as fair as you can by providing a fair amount of evidence for each case. For instance, you may plan to use a police detective as a witness for the prosecution and use him to introduce a murder weapon and to discuss the crime scene.
Expand each witness's testimony by writing a series of statements that the witness will be required to memorize. Include a description of what each witness saw. Add interesting facts for each witness, such as individual motives, things they don't want to say or contradictions in their testimony. Remember to make a list for your suspect as well. As an example, your detective may have found the murder weapon hidden on a tall mantle and he may not want to mention this, since the accused is only five feet tall.
Separate each witness's testimonies and give one to each witness. Copy the main statements on another paper and give this to each lawyer. Create other pieces of evidence, such as a picture of a knife for the murder weapon, pictures of a room where the murder may have occurred or important information about the weather from the evening in question. Provide this information to each lawyer.
Write the rules for your mock trial. Include a procedure for lawyers to address witnesses who forget their required lines or lie on the stand. Decide how long you want to give your lawyers to prepare and whether you want to give your lawyers a chance to do any pretrial interviews. Remember that it is your mock trial and you can change the rules as you need to give your students a fun an instructional courtroom experience.
Set up your classroom to represent your courtroom. Move your teacher's desk into the center of the room and place a chair next to your desk for the witnesses. Place your jury against a side wall, where they can clearly see the trial. Place two tables and chairs opposite of your desk for the prosecution and defense to sit. Instruct your jury to make the decision of guilt or innocence. You judge the overall court and each member's performance, grading each for their performance and preparation.