Maine Impeachment of Witness Testimony by Prior Conviction is a process by which a witness’s testimony may be challenged in a court of law in the state of Maine. Under Maine law, the credibility of a witness may be impeached if the witness has been convicted of a crime in the past. This type of impeachment is based on the idea that a person who has broken the law in the past may be less likely to tell the truth in a court of law. The types of Maine Impeachment of Witness Testimony by Prior Conviction include: 1. Evidence of the witness's conviction of a crime involving dishonesty or false statement. 2. Evidence of a prior conviction of a crime that is punishable by imprisonment in excess of one year and that is not a Class D or E crime. 3. Evidence that the witness has been convicted of a felony, or a misdemeanor involving the use of a deadly weapon. 4. Evidence that the witness has been convicted of more than three crimes of any kind, regardless of the nature or punishment for the crimes.