If you've been asked to write to the judge, use our sample character reference letter and fill-in-the-blank template. What's a character reference letter?A character letter is designed to show support for a defendant in a criminal case. These letters have the potential to influence the court. The character reference letter for court serves the purpose of offering the Judge insights into the Defendant's moral or mental attributes. Wondering how to write a character letter for sentencing? Following a few simple rules to writing a great letter. Dear Judge Mattison. Below is reference of what a letter should contain and a sample of a written letter for your use as a guide. We provide templates and tips on how to properly address a letter to a judge, ensuring your letter begins and ends with the appropriate formalities.