A character letter is designed to show support for a defendant in a criminal case. These letters have the potential to influence the court.Writing a character letter for a judge can be a daunting task. Here are nine essential tips for writing an effective sentencing letter. Introduce yourself in the opening paragraph. Defend a friend or family member's moral character in court. Use our Character Reference Letter for Court template to easily write your document. Below is reference of what a letter should contain and a sample of a written letter for your use as a guide. A character letter is a letter of support from people who know you to help show judges and DAs the positive sides of you. This is an action for a declaratory judgment of invalidity and non-infringement of U.S. Letters Patent 2,185,421.