Impeachment by Evidence of Untruthful Character is a legal process that can be used to discredit a witness during a trial. It involves introducing evidence of the witness' prior bad acts or prior statements that are inconsistent with the witness' current testimony. This type of impeachment can be used to show that the witness is not being truthful and thus not credible. Types of Impeachment by Evidence of Untruthful Character include prior inconsistent statements, prior criminal convictions, prior bad acts, prior civil suits, and bias or prejudice.