It is provided by G. L. c. 32, § 83, that “In every city, except Boston, which, by vote of its city council, accepts this section or has accepted corresponding provisions of earlier laws, the mayor and aldermen, or the board of police where such a board is established, shall, at his own request, or at the request of the chief or superintendent of police if, in the judgment of said board or officer, he is disabled for useful service in said department, retire from active service and place upon a pension roll any member of the police department of such city whom the city physician of such city certifies in writing to be permanently disabled, mentally or physically, by injuries sustained through no fault of his own in the actual performance of duty, from further performing duty as such member, or any member of said department who has performed faithful service therein for not less than twenty years continuously if, in the judgment of said board or officer, such member is disabled for *479useful service in the department; and every member so retired shall annually receive as a pension one half the amount of compensation received by him at his retirement, such amount to be paid by the city, which shall appropriate money therefor. The board of police, or the mayor in cities having no such board, may in an emergency call upon any person so pensioned for such temporary service in the department as he may be fitted to perform, and during such service he shall be entitled to full pay.” The answer to the petition does not deny that the city of Malden has accepted the provisions of G. L. c. 32, § 83, or of a prior statute containing similar provisions.
The office of police commissioner of the city was established by St. 1911, c. 16. By § 2 it is provided, “The police commissioner shall have authority to appoint, establish and organize the police of said city and to make all needful rules and regulations for its efficiency. Except as otherwise provided herein, all the powers and duties now conferred or imposed by law upon the mayor and aldermen of said city or upon the chief of police or city marshal relative to the appointment, pay, discipline, management, control, removal and retirement upon pension of the police of said city, are hereby conferred and imposed upon said police commissioner. . . .” By §5 it is provided, “Except as authorized by the city council of the city, said commissioner shall not increase the number of patrolmen; nor shall the pay of the members of the police force be increased or diminished, except by the concurrent action of the city council, mayor and police commissioner.”
It is not denied by the respondents that the petitioner on February 18, 1896, was duly appointed a regular officer of the police department and that he had performed faithful service continuously to April 1, 1926, a period of more than twenty years. The following facts could be warrantably found by the single justice, who had before him the auditor’s report, as well as additional evidence, introduced by the petitioner. While the petitioner had not been on duty constantly because of injuries sustained, or leave of absence without pay, he fell on the ice “on or about March 7,1926, ” *480while on duty, suffering injuries which required medical treatment, and on April 1, 1926, he made application under G. L. c. 32, § 83, for retirement to the police commissioner of the city on the ground that, having rendered faithful service to the city continuously for not less than twenty years, he had become disabled from performing useful service in the department by reason of physical disability as stated in a certificate of the city physician which was attached to the petition. The commissioner, acting on the certificate, which stated that the petitioner was permanently unable to perform the duties required of a patrolman in active duty because of his physical condition, granted the petition and retired the petitioner on a pension of one half of his present compensation, namely, “$l,012.87j/£,” to take effect as of April 1, 1926. The commissioner filed a certificate in which he specifically stated what had been done with his reasons for the action taken, and that “pursuant to the powers vested in me as Police Commissioner of the City of Malden, I hereby retire you, John J. Bushell, upon a pension of one-half of your present compensation, to wit, $1,012.87^ per year, the same to take effect as of April 7, 1926.” It further could be found that all the foregoing statements of fact were true.
The respondents’ requests for rulings five, six, seven, nine, ten, eleven, fifteen, sixteen, seventeen, and eighteen were denied rightly. Rich v. Mayor of Malden, 252 Mass. 213.
It is contended, that the commissioner exceeded his authority, and the proceedings were void. Whatever the law may have been as to the organization, control and management of the police department of the city prior to St. 1911, c. 16, that act provided in § 8 that “All existing acts and parts of acts inconsistent herewith shall not here- . after apply to the city of Malden,” and by § 2 the commissioner among other powers is expressly given authority to retire patrolmen on a pension. We find nothing repugnant in G. L. c. 32, § 83, to the exercise by him of the functions conferred by the statute.
It was uncontroverted that treasury warrants which were the pay rolls of the various departments of the city, for May, *481June and July, and September of 1926 included an item for the amount of the petitioner’s pension. The respondent, mayor of the city, however, refused in each instance to approve the warrant, because the petitioner’s pension was included. But, after the respondent city treasurer had made a notation on the warrants, “This amount includes pension of John J. Bushell. Am holding check, ” the mayor affixed his signature. The pension having been lawfully granted, the city was bound to pay it, and an action of contract therefor can be maintained by the petitioner, who was not removed from office, but transferred from active duty, subject to such temporary service as he might be able to perform. Mayor of Somerville v. Justices of the Police Court of Somerville, 220 Mass. 393, 396, and cases there cited. Rich v. Mayor of Malden, 252 Mass. 213, 217.
The first, second, third and fourth requests could not have been given.
We discover no error of law on the record except the refusal of the respondents’ nineteenth request, that the petitioner “has a full, complete and adequate remedy at law and is not entitled to have the issue herein raised heard and determined in this proceeding.” It should have been given. A writ of mandamus is not a matter of right, but is granted only to prevent a failure of justice where there is no other adequate remedy. Daly v. Mayor of Medford, 241 Mass. 336, 339, and cases there collected.
Exceptions sustained.