Under section 154 of Evidence Act, permission may properly be granted to a party to cross examine a witness of his over if the witness has given evidence unfavorable to the party, calling him, is correct there can be no stronger case of witness being unfavorable to a party than where the witness, by previously making a statement in favour of the party, has induced him to call him as his witness. Certain other provisions of the Indian Evidence Act, 1872, govern the use of such statements in a criminal trial, and thereby merit our attention. Section 141 of the Indian Evidence Act, 1872 defines leading questions, whereas Section 142 requires that leading questions must not be put to witness in an examination-in chief, or in a re-examination, except with the permission of the Court. The court can however permit leading questions as to the matters which are introductory or undisputed or which in its opinion have already been sufficiently proved. Section 154 authorizes the court in the discretion to permit the persons who call a witness to put any quest to him which might be put in cross examination by other party.