We see no valid reason for changing the rule, as it has long been settled and practised upon in this commonwealth, that a party calling a witness, even for formal proof of a written instrument, or of other preliminary matter, thereby makes him his witness. In such case, he cannot be permitted to impeach his general character for truth. Brown v. Bellows, 4 Pick. 194. Whitaker v. Salisbury, 15 Pick. 544. Nor can he put leading questions to him, unless permitted so to do by the court in the exercise of a sound discretion. Moody v. Rowell, 17 Pick. 498, 499.
It follows that the adverse party has the right to cross-examine the witness upon all matters material to the issue. Experience has shown that this rule is convenient and easy of application in practice, and works no disadvantage to the party who produces a witness. On the other hand, a different rule, by making it necessary for the court, during the examination of a witness, constantly to determine what is or is not new matter upon which the opposite party has the right to put leading questions, leads to confusion and delay in the progress of trials. The ruling of the court below in the present case was in conformity with our well established practice.
The argument, by which the counsel for the plaintiff sought to sustain the exceptions, that the judge declined to exercise his discretion concerning the right of the plaintiff to put leading questions to the witness, seems to us to be untenable. The ruling was not that the court might not, in its discretion, permit the witness to be so examined by the party producing him; but that it could not be claimed as a matter of legal right.
Exceptions overruled.