Rehabilitation of a witness is allowed only when it appears that the witness' credibility had been attacked. It is not allowed merely because there has been some rebuttal of the witness' testimony by other witnesses. Contradictory evidence to disprove the existence of the bias must be shown. This can take the form of testimony by the witness or by others. Rehabilitation for impeachment on poor reputation must show: Evidence of good reputation must be shown by other witnesses. Modern view: The rehabilitating witness may testify as to opinion. Federal view: The witness can show specific instances of honest conduct. Rehabilitate of a witness who has been impeached for a criminal conviction must show evidence of the witness' truthfulness. To rehabilitate a witness who has been impeached on prior inconsistent statements you must show: (1) Rebuttal by explanation of inconsistency or (2) Rebuttal by reputation evidence.