Opinion by
Mb. .Justice Gbeen,It was clearly proved on the trial, by direct and entirely uncontradicted evidence, that the act of the defendants in removing a portion of the house in question, was done in obedience to a positive, mandatory order of the commissioner of highways of the city of Pittsburgh. That order was given in conformity with the law as it then was. An ordinance for the opening of Kirkwood street, from Highland Avenue to Collins Avenue, had been regularly ordained and enacted by the city councils. •Viewers to assess damages and benefits had been regularly appointed, and had met and performed their duties, and made due report thereof according to law. After all this was done, the opening of the street was proceeded with until all obstructions were removed except the building in question. Preliminary notices had been given for the removal of the building, or a part of it, but the final and peremptory notice was not given *17until early in January, 1890. The matter of the opening and the probable removal of at least a part of the building had been known and talked of for several months before, and the plaintiffs had been in communication with the defendant Mellon in regard to it as early as October or November preceding. When the final order came in January for the removal of the building, it was an order which emanated from the proper officer, and it either had to be obeyed, or the city authorities would execute it at the expense of the owner. If he had refused to obey it and the proper officer of the city had removed the building, undoubtedly the city would be liable for the consequences to any person injured, if the law under which the act was done was a void law. But it is just as undoubted that the officer who obeyed his orders in removing the building would not have been liable for his acts of obedience to his orders.
In the case of Pittsburgh’s Petition, 138 Pa. 401, we decided not only that certain portions of the acts of 1887 and 1889, relating to streets and sewers in cities of the second class, were unconstitutional and void, but also that the city must pay for all work done under the proceedings, and for all damages inflicted upon property owners thereby. All the proceedings of the city for the opening of streets and assessment of damages and benefits, under the acts of 1887 and 1889, had at least color of authority under the language of those acts. If the real legal authority did not exist, because those acts were unconstitutional, the city would be responsible for the damages sustained by their proceedings. But it does not at all follow that the officers or agents who executed the authority of the city, in the premises, would be subject to any such responsibility.
The commissioner of highways was the proper officer, both defacto and de jure, for the execution of the orders of the city for the opening of streets, and could proceed with such execution without subjecting himself to a personal liability for his acts as such. He could not question the validity of his orders, and it was his duty to obey them. In the case of Clark v. Commonwealth, 29 Pa. 129, we held that even the acts of a president judge, whose right to his office was questioned, could not be impugned in any collateral proceeding. We said; *18“He is a judge defacto, and as against all parties but the commonwealth he is a judge de jure also.” In the case of Campbell v. Commonwealth, 96 Pa. 344, we enforced the same doctrine, saying, in relation to the challenged title of two associate judges: “Under due form of law, they hold their offices by' title regular -on its face. They aré performing the duties thereby imposed on them, and enjoying the profits and emoluments thereof. Thus they are judges de facto, and as against all parties but the commonwealth they are judges de jure. Having at least a colorable title to these offices, their right thereto cannot be questioned in any other form than by quo warranto at the suit of the commonwealth.” In both of the foregoing cases, we refused to permit the validity of the acts done by the judges to be called in question in any collateral proceeding.
It is no doubt true that unconstitutional laws cannot confer either contract rights, or property rights, upon any persons, natural or artificial, and the validity of such laws may be directly questioned by any persons adversely interested. But that doctrine is not in conflict with the question which arises in this case. Here, the question is as to the immunity from personal liability of a citizen who acts as the mere representative of a municipal officer, in the performance of a duty which, apparently and by color of law, rested upon him as a citizen, and which would necessarily be performed by the municipal officer without any personal liability, if the citizen refused to obey the law and the mandate of the officer. If, in such circumstances, the municipal officer would be exempt from individual liability for executing the orders of the city, we know of no reason why the citizen should be subject to such liability, he being a person interested, and apparently subject to the duty of obeying the mandatory order of the authorities. No hardship results to the persons injured, as they have their recourse to the city, and it would be a severe hardship to hold the citizen liable for merely obeying the law as it is written.
Judgment reversed. C.