"Learn how to craft an effective character reference letter for court proceedings with our comprehensive guide. Sample Format for a Character Letter.If you have been asked to write a character letter, this simple template may be a useful guide. A character letter to a judge should establish your credibility, paint a full picture of the defendant and be respectful, among other things. Use a formal email address, preferably one that includes your full name. In this article, we will discuss how to write a formal letter to a judge, along with the proper format and a sample letter. Sample of a Character Reference Letter. Do provide honest and accurate details regarding their character.