A character letter plays a dual role. Use specific examples of when you observed the defendant's good character.Describe a time you saw the defendant go out of his way to help someone in need. Sample Format for a Character Letter. If you have been asked to write a character letter, this simple template may be a useful guide. The character reference letter for court serves the purpose of offering the Judge insights into the Defendant's moral or mental attributes. The best character letters often begin with the writer explaining who he or she is and what he or she does. The character reference letter for court serves the purpose of offering the Judge insights into the Defendant's moral or mental attributes. The background of the person writing the character reference letter can be its most persuasive element. I am writing this letter to offer a more complete picture of who_____ is as a person.