delivered the opinion of the court, October 6,1884.

This ejectment was brought 10th February 1882, by Israel C. Caldwell against Joseph Bell and Thomas Murphy. On the 6th September 1883, a nonsuit was entered as to Thomas Murphy and on the 18th of the same month, W. Patterson *48Bell presented his petition, for leave to defend; bis application was refused, and the refusal is assigned for error. The petitioner put his application upon the ground that he was in possession of the premises, at the institution of the suit, as the tenant of Thomas Murphy; that on the 31st of August preceding his application, by a conveyance of the title from Thomas Murphy, he became the owner in fee of the premises in dispute, and that Joseph Bell prior to the suit, and since, occupied under him as a mere tenant at will.

In McClay v. Benedict, 1 Rawle, 424, it is stated, that “ the admission of a party claiming right to defend, is clearly an act of the court, whose duty it is, to inquire before making the order, whether the applicant stands in the relation of landlord or whether his claim of title is consistent with the possession of the occupier. It is not every person who claims to be a landlord that really is such, nor is it every claim of title which gives right to defend the suit.” The rights of the original parties to the record must be regarded and when the party desiring to defend exhibits a title inconsistent with the possession of the tenant he cannot be joined in the action, and if so joined, when the inconsistency of his title appears it may be refused, and his name stricken from the record : McClay v. Benedict, supra; Adams on Ejectment, 232; Linderman v. Berg, 2 Jones 301; Boyer v. Smith, 5 Watts 56.

Where, however, no such inconsistency appears, or the relation of landlord and tenant subsists, unless the effect of the application is to cause unreasonable delay, the Act of Assembly is to be taken as mandatory, not merely permissive. The power to be exercised by the courts, in this behalf, is in the interests of public justice, and although the language of the statute is merely permissive in form, yet as public as well as private interests call for its exercise, it must be considered as mandatory: Mason v. Fearson, 9 Howard, 248; Supervisor v. U. S., 4 Wallace, 435; Commonwealth v. Gable, 7 S. & R., 425 ; Commonwealth v. Pittsburg, 10 Casey, 513; Dwarris on Statutes, 220; Sedgwick, 316. The refusal of this right, in a proper case, is therefore assignable for error.

As the case is here presented, we must determine the right of the petitioner upon the facts set forth in his petition ; no answer was filed, and the facts are not otherwise denied. The title of W. Patterson Bell is identical with that of Thomas Murphy, who was originally joined in the action; adding his name as a party, with leave to defend the action jointly with Joseph Bell, produces no inconvenience to the plaintiff, and raises no other issue beyond what was originally involved. The ground of the defence is in no way changed, and no surprise is practised. According to'the recitals in the peti-*49lion, and the purport of the offers made at the trial, Joseph Bell was the tenant of his son at the time this suit was brought and over since, he held the premises rent free by the mere permission and allowance of his son, and was therefore a tenant at will, he had no claim to the land, either in title or possession, which was the subject of sale. The possession of Joseph Bell, under such circumstances, was the possession of his son, and that merely permissive possession was entitled to the protection of the landlord’s title.

W. Patterson Bell was in the actual possession of the premises, at the service of the writ, it should have been served upon him, and his name entered upon the record as a defendant. He was then, however, a tenant for years, and his landlord was a party to the action. The tenant’s possession was involved in the contest of the title, ho had no rights which were not identical with those of his landlord, who was the real and substantial party; the tenant, in such case, might well deem it unnecessary to join in the defence. It was the entry of the nonsuit by the plaintiff which developed the duty of W. Patterson Bell to defend. If the defendant had not suffered nonsuit, the possession of Joseph Bell might have been vindicated by the exhibition of his co-defendant’s title: by the mere juggle of a nonsuit it is attempted to exclude all evidence of the title upon which that possession might be defended.

We can discover no good reason why the petition of W. Patterson Bell should not have been allowed; the order refusing him leave to be admitted to defend must therefore be reversed. As the offer of evidence, the refusal of which constitutes the first assignment of error, becomes clearly admissible in this condition of the cause, we will not consider it in the connection in which it was made.

The order of 26th November, 1883, refusing the application of W. Patterson Bell for permission to defend, is reversed; and it is ordered that the application be allowed.

The judgment is reversed, and a venire facias de novo is awarded.