self-serving
adj. referring to a question asked of a party to a lawsuit or a statement by that person that serves no purpose and provides no evidence, but only argues or reinforces the legal position of that party. Example: Question asked by a lawyer of his own client: "Are you the sort of person who would never do anything dishonest?" Such a question may be objected to as "self-serving" by the opposing lawyer and will be disallowed by the judge, unless there is some evidentiary value. Some people add self-serving comments to their testimony, such as "I never tell lies," which can be stricken from the record as a self-serving declaration.