I. Ve neither discuss or decide the question respecting parties, because our ruling upon the demurrer disposes of the entire case. As to a kindred question relating to parties, see the discussion in the case of Fleming v. Mershon, 36 Iowa, 414; 7 West. Jur. 309, et seq.
II. It is averred that the petition for the election to vote the tax was not signed by one-third of the resident tax payers of the township, as the law requires. This is followed by the averment that the incorporated town of Leon is situated within Center township, and that half the signers to the petition resided in said town. Our statute (ch. 102, Acts 1870; authorizes “ any township, incorporated town or city to aid,” etc. Whenever the aid is proposed by a township any resident tax payer therein may petition for, and any legal voter therein may vote at the election to determine the question of aid, even if such petitioner or voter also resides within any incorporated town or city embraced within the limits of such township. Often in law, as always in mathematics, the greater includes the less. If, therefore, it was intended only to aver that the petition was insufficient because signed by residents of the town, the averment would show the petition sufficient.
But if, in fact, the petition was not signed by one-third of the resident tax payers of the township, nevertheless, we hold that after the trustees have decided that it was signed by the required one-third and have ordered the election which has been held, the aid voted and tax levied pursuant to it, the validity of such tax cannot be assailed on the ground that the petition was not signed by the requisite number of tax payers. That fact can be re-examined and again decided only upon an *81appeal, writ of error, certiora/ri, or other method provided for a direct review of the decision made by the trustees. The decision of that question by the trustees is judicial; and since the statute gives them express and undoubted jurisdiction to determine it, their judgment becomes, like every other judicial determination, conclusive until reversed or set aside by a direct proceeding in the manner provided by law. It cannot be assailed indirectly or collaterally, as is sought to be done in this case.
The petition for the vote stands in substantially the same relation to the subsequent proceedings as an original notice or summons does to the proceedings which it inaugurates. If it is defective in fact, but is adjuged sufficient by the tribunal having jurisdiction to decide upon it, such adjudication becomes conclusive until reversed or set aside upon an appeal, writ of error, certiorari, or the like. This has been, in effect, so ruled by this court. Cooper v. Sunderland, 3 Iowa, 114; Morrow v. Weed, 4 id. 77; Dishon v. Smith, 10 id. 212, and many other cases, besides numerous authorities in other States, some of which are cited by counsel for appellee.
The question here is essentially different from that arising in eases where a city council is authorized to order the pavement of a street or sidewalk upon the petition of a third, half or two-thirds, or other proportion of the property-holders. There, only the existence and presentation in fact of such a petition gives the council jurisdiction to proceed, and becomes the only basis of their action. Here the bare presentation of a petition confers upon the trustees jurisdiction to determine its sufficiency, and all other matters dependent thereon. In the one case, the fact gives jurisdiction ; in the other, the petition gives jurisdiction. In either case, whenever jurisdiction attaches, the adjudications following are conclusive against collateral attacks, and may only be assailed directly in the manner provided by law.
The exhibit shows that the tax was duly levied; and there is no such averment of facts as constitutes vitiating fraud.
Affirmed.