This petition for a prerogative writ of prohibition was brought by Edward J. Costello and the Housing Authority of the City of Pawtucket, Rhode Island, to prohibit and enjoin the respondent Lawrence A. McCarthy, as mayor of said city, from holding a hearing, called by him for October 28, 1952, to determine the eligibility of said Edward J. Costello to serve as a commissioner of such housing authority. Upon the filing of this petition, citation was issued to the respondent giving notice that he was enjoined and restrained until further order of this court from holding the hearing above referred to.

After the cause was argued in this court on December 5, 1952 and before our decision thereon, the respondent on December 8 filed in the office of the city clerk of Pawtucket a “Declaration Of Vacancy,” in which he asserted that the last appointment, on July 14, 1950, of said Edward J. Costello as a member of the housing authority was a nullity, on the ground that he was ineligible for such appointment because he was not then or at any time thereafter an elector of the city of Pawtucket, but was, on his own sworn statement, at the time of such purported appointment and continuously thereafter an elector of the town of East Providence in this state.

On the same date, December 8, 1952, respondent filed in the office of the city clerk an instrument in writing purporting to appoint Edward P. Powers a member of such housing authority to succeed Edward J. Costello as a commissioner thereof, to hold office until July 14, 1955 and until his successor should be appointed and qualified.

Thereafter the State of Rhode Island through the attorney *390general at the' relation of Edward J. Costello and the housing authority filed in this court a petition in equity in the nature of quo warranto to determine whether the relator Edward J. Costello or Edward F. Powers is entitled to the office of commissioner of said housing authority. That petition has been argued before us and is now pending for decision.

Since it now appears from a consideration of the briefs and arguments therein that the determination of such petition will not only decide the respective rights of the petitioner Edward J. Costello and the respondent mayor, Lawrence A. McCarthy, but also will determine the ultimate and underlying question whether Edward J. Costello or Edward F. Powers is entitled to hold the office of commissioner of said housing authority, we are of the opinion that the issue presented in the instant case has become moot and therefore our decision thereon is unnecessary.

The instant petition for a writ of prohibition is accordingly denied.