This is an action to recover for personal property sold and delivered by the plaintiff to the defendants. The defendant Amsbaugh appeared and filed an answer denying the allegations of the complaint. The summons was duly served upon McKinley, the other defendant, but he failed to answer. A jury trial was had, and the following verdict was rendered: “ We, the jury, find for the plaintiff four hundred and fifty dollars,” and thereupon a judgment was entered in favor of the plaintiff, against the defendant Amsbaugh, *574 for that sum, and costs. Amsbaugh moved for a new trial, which was denied, and he takes this appeal from the judgment and the order refusing the new trial.

At the trial the plaintiff called the defendant McKinley, as a witness, to prove that himself and Amsbaugh were partners, and as such purchased the property sued for, to which the defendant Amsbaugh objected that the witness was not admissible to prove those facts, being interested, but the Court overruled the objection, and allowed him to testify, and Amsbaugh excepted, and this ruling of the Court is one of the grounds of error assigned by the appellant.

In the case of Washburn v. Alden, ( 5 Cal. 463 ) it was held, that a defendant who has suffered default is not a competent witness to prove that he was authorized by his co-defendants to sign his name to a note, as by so doing he would reduce the amount of judgment against himself. (See also, Easterly vs. Bassignano, 20 Cal. 489 .) So in the present case, McKinley was not competent to prove that Amsbaugh was a partner in the purchase of the property, because he would thereby cast a part of the burden of the debt from himself upon his co-defendant. He would thus gain “ by the direct legal operation and effect of the judgment,” and therefore comes clearly within the provisions of Sec. 393 of the Practice Act. He would be a competent witness to prove that his co-defendant was not his partner; for this, in a legal point of view, would be against his interest. (Sparks v. Kohler, 3 Cal. 299 .)

Upon the cross-examination of McKinley, he testified that the debt sued for had been paid and satisfied. The plaintiff objected to this evidence, and also to the evidence of Amsbaugh, who was examined under notice upon the same point, that it was not admissible, as the defendant had not plead the same in his answer. The Court allowed McKinley’s evidence on that point, but excluded that of Amsbaugh. The defendant then asked leave to amend his answer to set up the plea of payment, which was refused by the Court, and to which he excepted. The exclusion of this evidence and the refusal to allow defendant to amend his answer are also assigned as error. The evidence must be confined to the matters put in issue by the pleadings; but it has been held by this Court, *575 in Frish v. Caler ( 21 Cal. 71 ), that a plea of payment is not new matter, and it follows, that it was not necessary to set it up as a special defense in the answer. The evidence was therefore admissible under the general denials of the answer, and the Court therefore erred in excluding it.

The judgment is reversed, and the cause is remanded for further proceedings.