¶1delivered the opinion of the court.
¶2Pedro Hernández Villanueva brought an action of unlawful detainer in tenancy at .sufferance in the District Court of Aguadilla against Pablo Rosado Vargas and Rufina Gonzalez Vélez, praying for their eviction from a property of eight cuerdas of land situated in the ward of Coto of Isabela of which he is the owner, and the defendants not having appeared at the preliminary hearing prescribed by law in this class of actions, the court rendered judgment for the plaintiff ordering the eviction of the defendants.
¶3Two months after the judgment had been executed against Rufina González only, Pablo Rosado no.t having been found on the property, both defendants filed a motion playing the court to set aside the judgment in the proceeding. The motion of Pablo Rosado was based on the ground that the court had not acquired jurisdiction over his person, because it was not shown in the marshal’s return on the summons that Ru-fina González, on whom substituted service was made in his *362absence,, was the person in charge of the property, and further, because judgment had been rendered without any title of ownership having been exhibited by the plaintiff and only on the warning contained in the summons. Butina Gonzá-lez on her part moved the court that in view of the facts set up in an affidavit accompanying the motion it exercise the dis-cretional power conferred upon it by section 140 of the Code of Civil Procedure and set aside the judgment rendered as well as its execution. The said affidavit was sworn to by Butina González before Augusto Suárez, Justice of the Peace of Isabela, and avers that she is a feme sole and for more than thirteen years has lived in concubinage with Pablo Bosado, by whom she has had several children; that an action of unlawful detainer has been brought against both to evict them from a property on which she lives with her children; that she does not know how to read or write and, therefore, could not understand the papers left at her house when she was summoned, and that it was not possible .for her to hand them to Pablo Bosado until six days later because he works away from the property and it is his custom to come to see her and her, children every six or eight days; that the property upon which the action was brought belongs to her, she having bought seven cuerdas of it with the aid of Pablo Bosado and inherited the remaining cuerda from her mother; that one year has not elapsed since the judgment was rendered, and that she has a good defense.
¶4In view of these motions and after the parties had been heard the court rendered a decision holding that the service of the summons upon defendant Pablo Bosado and other proceedings, including the eviction of the defendants, particularly the judgment by default sustaining the action of unlawful detainer, were void, setting aside the said judgment and ordering the plaintiff and the defendants to appear on a specified date and that the defendants be reinstated in the possession of the property on which the said proceedings were *363brought until the case should be again heard and the proper judgment rendered.
¶5From that decision the plaintiff took the present appeal in which the respondents have not appeared.
¶6» The first error which the appellant attributes to the court a quo consists in its having allowed the affidavit filed by Bufina González tó influence its decision when the same is null and void because sworn to before the Justice of the Peace of Isabela who is not authorized to administer such oaths, according to the Act establishing a registry of affidavits executed before notaries and other officers, approved March 12, 1908.
¶7In the case .of Esteban Lópes Cruz v. Serafín Meléndes decided March 9, 1915, we held that municipal judges are empowered to administer affidavits, in conformity with section 4 of the Act of 1908 establishing a registry of affidavits, which is left in force by Act No. 13 of March 9, 1910, when such affidavits refer to matters of public and not private interests. The same is true of affidavits made before justices of the peace, and as the affidavit sworn to by Bufina González before the Justice of the Peace of Isabela did not refer to matters of private interest (in which case only a notary could have administered it), as it was intended for use in a judicial proceeding, we cannot hold that the said affidavit is null and void. The chief object of an affidavit is for court purposes. Delgado v. The Registrar of Caguas, decided February 19, 1915.
¶8The second assignment of error is that the allegations of Pablo Bosado are not sufficient to support the judgment appealed from; for, as it appears from the affidavit of Bufina González that Pablo Bosado lives with her in concubinage on the property which is the subject-matter of the action of unlawful detainer, she was the person in charge of the said property.
¶9However, if the service of the summons is so defective that the court could not acquire jurisdiction over the per*364son of defendant’Pablo Posado because the return did not contain what the law requires for that purpose, then the judgment rendered by the court without jurisdiction is null and void and the facts subsequently adduced, to correct the service are immaterial.
¶10In the return on the summons served on Pablo Posado the marshal certified that he had personally served “ Pufina Gon-zález, being- unable to find Pablo Posado Vargas at his residence, which is also the residence of the said Rufina Gonzalez, by handing to and leaving with the said Pufina González personally, at her residence, a copy of the said summons together with a true and exact copy of the complaint filed in the said action and referred to in the said summons.”
¶11Section 5 of the Unlawful Detainer Act provides that if the defendant cannot be found at the place of trial, or if he resides elsewhere, the summons shall be served upon the person who in his name is in any way in charge of the property at said place. Not being able to find Pablo Rosado, in this case the summons was served on Rufina González, but it was not set out that the service was made upon her because she was in charge of the property in his name, or in what manner she was in charge, which requisite it was necessary to state in the return on the suimnons in order that the court might know that the formalities required by law in such cases having been.complied with, it had acquired jurisdiction over the person of said defendant; and the statement that she resided at the same place as Pablo Rosado is not enough to cure that defect, because this fact is not sufficient to justify the inference that she was in charge of the property in his name.
¶12In view of these facts, we cannot hold that the jower court committed the error alleged as the second ground of appeal.
¶13The third ground of appeal is based on an alleged error committed by the court in admitting and ruling upon a motion by Rosado which is frivolous, inasmuch as Pufina González being the sole owner of the property, according to her affi*365davit, Pablo Rosado bas no interest whatever therein. Aéide from the fact that Rufina Gronzález has not declared that she is the solé owner, but' on the contrary deposed that she had purchased seven cuerdas with the aid of Pablo Rosado and he having been sued and judgment having'been rendered against hini, he is entitled in any event to have the judgment set aside for it was rendered without jurisdiction, and .we cannot hold that his motion on such ground is frivolous.
¶14Nor can the fourth assignment of error be sustained because as an action of unlawful detainer cannot prosper when a question of title to the property is raised, as has been held repeatedly by this court, from the moment when Rufina Gon-zález swore that the property which is the subject-matter of the action of unlawful detainer belonged to her, partly through inheritance and partly by purchase with Pablo Ro-sado, we do not see that the lower court abused the discre-tional power conferred upon it by section 140 of the Code of Civil Procedure to set aside a judgment by default in giving. the defendant the opportunity requested to show that she has some title which may defeat the action of unlawful detainer, the moré so in this case where the judgment is clearly null and void as to the other defendant.
¶15In view of the conclusions which we have reached on the foreg'oing grounds of appeal and inasmuch as the proceedings subsequent to tlie summons and the judgment are void, it is not necessary to consider the fifth assignment of error, which is that there wás error in the trial which is annulled.
¶16The sixth error alleged is principally, that the defendants did not file affidavits of merit with their motions so that the judge might exercise the discretional powers coiiferred upon him by section .140 to set aside a judgment.
¶17. Pablo Rosado did not base his motion upon that section and if such affidavit be necessary as to the other defendant, we are of the opinion that the affidavit she filed was sufficient for that purpose:
¶18The seventh and last assignment is that there was error *366in setting aside a judgment which does not create a presumption of res judicata.
¶19It is true that judgments in actions of unlawful detainer do not prevent the litigation of the ownership of the properties in other actions, nevertheless a judgment which is null and void for lack of jurisdiction over the person of the defendant should not he allowed to stand simply because the question of ownership can be raised later. Moreover, a judgment of unlawful detainer changes the possession of the property.
¶20Therefore, as we can see no reason for reversing the decision appealed from it should he *
¶21Affirmed.