delivered the opinion of the Court. The only question to be considered is whether Jaques was a competent witness.

This question was fully argued, but not decided, in Winship v. The Bank of the United Stales, 5 Peters, 529, the Court being divided in opinion as to this point. The arguments in that case, arid the authorities cited, have been re ferred to by counsel, and considered by this Court, and upon the whole, we are of opinion that Jaques was a competent witness.

The objection to the competency of the. witness is, that he was interested in the event of the suit, because, after the making of the notes sued, Winship gave to the witness a general release of all liabilities to him on account of these notes ; and it is argued, that if the plaintiff should recover in this action the defendants could not recover over against the witness, whereas he would remain liable to the plaintiff if he should fail to recover against the defendants.

Several answers have been given to this objection. First, it is said, that the interest of the witness, if any, was created by the act of the defendants, after the plaintiff had become entitled to his testimony. The cases cited on this point are such as show management by one of the parties to deprive the other party of the benefit of testimony, as by laying a wagei with the witness as to the event of the suit, or where a wit ness has a like wager with another, without the consent of the party entitled to his testimony, and the like. In such cases, it would be against the manifest principles of justice to allow *47a witness thus to disqualify himself. But the reason does not apply to a case like the present, in which the witness acquired an interest, such as it was, by a fair bond fide contract in the course of business, without any intention on the part of the defendants or the witness to deprive the plaintiff of the ben efit of his testimony. This distinction is noticed by Lord Ellenborough in Forrester v. Pigou, 1 Maule & Selw. 14, and is founded on the plainest reasons.

In the second place, it was objected to the operation of the release, that the defendants or Winship, at the time, had no demand against the witness, upon which the release could operate. This may be true, but perhaps the release might well operate by way of estoppel or some other way ; but as to this we give no opinion, because we think, that the remaining answer to the defendants’ objection is decisive.

For, admitting that the release discharged the witness from his liability to the defendants, still he is not interested in the event of this suit. He will be still liable to the plaintiff, whether he recovers judgment against the defendants or not; and it is clear, that the judgment in this suit cannot be given in evidence in an action against the witness. It is said, that it is to be presumed the plaintiff will follow up his legal rights, and if he should recover judgment he will obtain satisfaction. But we do not even know, that he will be able to obtain satisfaction ; the defendants may become insolvent, though, in this particular case, there is no reason to suppose they will ; but the question of the competency of the witness is not to be determined by the solvency or insolvency of the defendants. It is not a question what will be the probable effect of a recovery by the plaintiff, but what will be its immediate and certain effect upon the witness’s liabilities ; for if the interest is contingent and uncertain, it will go to the credit of the witness, and not to his competency. 2 Stark. Evid. 745. It is also said, that the distinction taken by the plaintiff’s counsel is new and unsupported by the authorities. It may be, that there is no case precisely in point, but the principle, on which the distinction is founded, has been frequently recognised. The interest, which the witness Jaques had, was similar to that of a co-trespasser, and it is perfectly *48well settled, that in an action of trespass against one of several trespassers, a co-trespasser may be admitted as a witness for either party. Blackett v. Weir, 5 Barn. & Cressw. 387 ; Hall v. Curzon, 9 Barn. & Cressw. 646. Indeed the interest of a co-trespasser is much stronger, if it be true, as Lord Tenterden says, that a recovery against one of several co-trespassers is a bar against the others. If the law were so, it would be difficult to discover any good ground, on which a co-trespasser could be admitted as a witness for the plaintiff ; for he would be directly interested in the event of the suit, as by the plaintiff’s recovering judgment he would be discharged from a liability. But I apprehend, that the law is now well settled, as laid down by Lord Ellenborough in the case of Drake v. Mitchell, 3 East, 258. He says, a judg ment recovered in any form of action, is but a security for the original cause of action, until it be made productive in satisfaction to the party ; and, therefore, till then, it cannot operate to change any other collateral concurrent remedy, which the party may have. This point is considered in Campbell v. Phelps, 1 Pick. 70 ; and is ably discussed in a note by Mr. Metcalf, in Yelverton, 68. But this point is immaterial in the present case, as it is well settled that a co-trespasser may be admitted to prove, that he did the act by the command of the defendant ; and it is clear, that Jaques had not a greater or more certain interest in the event of the suit, than a co-trespasser would have in an action of trespass, he not being a party. The recovery by the plaintiff cannot, without satisfaction, discharge Jaques from his liability, whatever may be the law in regard to a recovery by the plaintiff in an action of trespass against one of several co-trespassers. He was not, therefore, interested m the event of the suit ; but if he were under any bias, it was an objection to his credibility, and not to his competency.

Judgment according to verdict.