The credibility of a witness may be attacked by any party, including the party calling the witness, except that the credibility of a witness may be attacked by the party calling the witness by means of a prior inconsistent statement only upon a showing of affirmative damage. The foregoing exception does not apply to statements admitted pursuant to Rules 801(d)(1)(A), 801(d)(1)(B), 801(d)(2), or 803.
Ill. R. Evid. 607