SiebeckeR, J.
Plaintiff seeks to set aside a conveyance of real estate executed by him on May 2, 1902, to Margaret Hagan, upon the ground that it was fraudulently obtained from him. He also asks that a mortgage executed by his deceased wife upon part of the premises which he claims to own be reformed by reducing the consideration from $300, the amount expressed in the mortgage, to the sum of $100, the amount alleged to have been the true consideration for the mortgage. It appears that at the time the action was commenced against Margaret Hagan she held title to the premises under the deed from plaintiff and that she was the owner of the note secured by the mortgage given by plaintiff’s wife on part of the real estate in controversy. It also appears that Margaret Hagan died during the pendency of the action, that she left a will of which Thomas McDermott is the executor, and that she left two minor children as her *494heirs. After her decease the action was revived in the name of her executor, and in such representative capacity he was substituted as defendant and was authorized to defend the action as executor. We are not informed whether or not Margaret Hagan made disposition of this real estate by her will, nor is it shown whether she left any debts to be paid out of this real estate which would authorize the executor to take possession thereof for this purpose. The record is therefore barren of information as to the persons in whom the title to this real estate vested at the time of Margaret Ha-gan’s death; but it is certain that such owners, whoever they may be, are not parties to this action. Under sec. 2604, Stats. (1898), such persons are necessary parties to determine the issues raised by the action for cancellation of the deed from plaintiff to Margaret Hagan, and should have been made parties under sec. 2610, Stats. (1898), that there might be a complete determination of the controversies presented in the action. Zœgel v. Kuster, 51 Wis. 31, 7 N. W. 781; Jones v. Graham, 80 Wis. 6, 49 N. W. 122. The effect of such defect of parties on the judgment in the action was considered and determined in the recent case of McDougald v. New= Richmond R. M. Co. 125 Wis. 121, 103 N. W. 244, and it was held that where the interests of absent parties are necessarily involved with those of the parties before the court, and where no adjudication could be entered in respect thereto without also adjudicating, to some extent at least, the rights of others interested in- the subject matter of the cause of action who were not parties before the court, such a situation prohibited determination of the controversy in their absence, and no judgment could properly be awarded until such interested parties were brought into the action to have their rights adjudged. A judgment rendered in their absence would be erroneous upon the ground that it violated a statutory command and constituted “jurisdictional error, in the sense of inexcusably departing from *495established principles respecting the exercise of judicial power,” and would render the judgment “erroneous upon grounds which may be raised at any time while the court has control of the case.” McDougald v. New Richmond R. M. Co. 125 Wis. 121, 130, 103 N. W. 247. Upon this ground the judgment in this case cannot be sustained, since it attempts to cancel the deed given to Margaret Hagan without the persons who became vested with the title at the time of her death being parties to the action.
The relief demanded — a reformation of the mortgage so as to reduce the consideration therein expressed — is necessarily dependent upon the cancellation of the deed; for, if the deed stands, plaintiff has no standing to attack the mortgage upon the land. Such a situation would leave him without any interest in the land. The court, however, determined this question upon the ground that the deed ought to be canceled and the title to the mortgaged property restored to the plaintiff. Though no judgment can be awarded upon the issues for the reason above stated, it is proper to look into the evidence to ascertain whether it supports the court’s conclusion of fact as to the mortgage transaction. This issue of fact was litigated between the plaintiff and the executor, who properly represents the estate of Margaret Ha-gan for this purpose. Well-nigh all the material evidence on the question of the actual consideration for the note and mortgage so given by the plaintiff’s deceased wife to Margaret Hagan is a narrative hy plaintiff of communications pertaining to transactions between himself and his son John and his son’s wife, Margaret Hagan, who are both deceased. This evidence was objected to as incompetent under sec. 4069, Stats. (1898). Plaintiff’s incompetency as a witness to the giving of such testimony is too plain and clear for argument under the circumstances presented. The substance of plaintiff’s evidence related to communications and transactions with these deceased persons, concerning which *496the opposite party had given no evidence. The evidence was received subject to objection, but evidently the court relied on it in its conclusion of fact, since there is no other evidence in support of the court’s finding. The admission of such evidence subject to objection cannot be indorsed as good practice under the circumstances of this case. It was perfectly plain when the evidence was offered that it was objectionable upon the ground stated, and there was no suggestion that it could become competent through circumstances not then disclosed. The reception of clearly incompetent evidence is a practice which leads to confusion in the trial, casts the burden of meeting such incompetent evidence upon the opposite party, and is liable to entail useless expense of money and waste of time in fruitless inquiry. The evil consequences which may follow from such a practice are sufficient to condemn it, and require calling attention of the trial court thereto. Aside from such incompetent evidence there is only the statement of Mr. O’Hare that John Hagan, the husband of Margaret Hagan, stated to him that the actual consideration for the note and mortgage was $150 instead of $300, the amount specified in the instrument. This statement was made at a time long subsequent to the transaction, and, moreover, there is no proof that he acted as her agent in the transactions of this loan. Hnder these circumstances we must hold that the evidence wholly fails to sustain the findings of the trial court on this issue and that the judgment awarded is not supported.
By the Court. — Judgment reversed, and the cause remanded for further proceedings according to law.