Cross examination is the interrogation of a witness espousing the cause of the opponent.
The purpose of cross examination is to extract favorable facts from the witness or to cast doubt on his credibility to dilute the weight of unfavorable testimony.
The cross examining attorney is not allowed to ask questions not related to facts revealed in direct examination. The cross cannot go beyond the domain set by direct examination except to the extent required to impeach the credibility or reputation of the witness.
Unlike in direct examination a leading question may be asked in cross examination.