Party may not impeach his own witness.
Section 340
SEC. 340. Party may not impeach his own witness. — The party producing a witness is not allowed to impeach his credit by evidence of bad character, but may contradict him by other evidence, and in the discretion of the court, in order to show that the witness has misled him into calling him to the stand, may also show that he has made at other times statements inconsistent with present testimony.