The opinion of the court was delivered by
Schettino, J.This is a class action for a declaratory judgment and for ancillary injunctive relief in which plaintiffs, duly appointed and regularly employed court attendants in Bergen County, seek a determination that defendant sheriff could not lawfully transfer plaintiffs and other court attendants similarly situated to the county jail to act as jail keepers. The defendant admits such transfers for temporary periods of not more than ten days to two weeks when regularly employed personnel in the jail were not available for such duties. The trial court denied plaintiffs’ motion for summary judgment and granted defendant’s countermotion for dismissal of the complaint on the ground that plaintiffs failed to exhaust their administrative remedies.
The Appellate Division reversed. It found that plaintiffs’ administrative remedies need not have been exhausted because the matter turned solely on a question of law, i. e., a statutory construction of N. J. S. 2A:ll-32, which provides for and defines the duties of court attendants. Finding their duties restricted by the statute to those of a constable attending court, the Appellate Division reviewed the practice of having *317constables, and now court attendants, attend the courts, and by contrasting their duties with those of jail keepers, concluded that the statutory duties of the position of court attendant do not encompass service in the county jails as keepers thereof, nor permit the transfer of attendants to the latter position, even for a temporary period. 74 N. J. Super. 128, 136-137 (1962). We granted certification on defendant’s petition. 38 N. J. 179 (1962).
Court attendants are appointed by the sheriff of each county to attend upon the law division of the superior court and the county court in their county and to perform those duties which were performed by constables when summoned to attend such courts. N. J. S. 2A:ll-32. In addition, all court attendants in the competitive class of civil service have, by virtue of their appointment, the power to act as officers for the detection, apprehension, arrest and conviction of offenders against the law. N. J. S. 2A:15A-3. Jail keepers in Bergen County, also appointed by the sheriff, are responsible for proper maintenance and protection of jails under his jurisdiction and for the custody and keeping of prisoners confined therein, and have the same power and authority as constables. N. J. S. A. 30:8 — 18. Both court attendants and jail keepers are in the competitive class of civil service and have been classified separately.
Erom time immemorial, the general duty of all constables, both in England and the United States, was to keep peace within their respective districts, 1 Blaclcstone, Commentaries 355-56 (Chitty ed. 1895), although in time they acquired other duties, usually in connection with the judicial process. Thus, constables have been called upon to serve writs, attend the sessions of designated courts, take custody of juries and discharge other functions assigned to them by statute. See Allor v. Board of Auditors, 43 Mich. 76, 4 N. W. 492 (Sup. Ct. 1880); Rich v. Industrial Comm’n., 80 Utah 511, 15 P. 2d 641 (Sup. Ct. 1932); 4 Holdsworth, A History of English Law 122 — 25, 156 (1924). And New Jersey was no exception. The constable’s oath has not changed in over 160 *318years (compare Paterson, Laws (1800), p. 286, .with R. S. 40:41-39) and attests to his three-fold position as conservator of the peace, civil officer, and ministerial officer of the courts. See Ewing, A Treatise on the Office and Duty of Justice of the Peace, etc., 190-95 (1805). The latter duties were in evidence in the colony of East Jersey as early as 1678. Cox v. Passaic Common Pleas, 45 N. J. L. 328 (Sup. Ct. 1883).
Although historically both the constable and sheriff were peace officers, they were separate institutions, and all responsibility connected with the jails fell to the sheriff, with the jailer being but the sheriff’s agent. 1 Blaclcstone, supra, at pp. 343-46. Early New Jersey statutes also indicate that the office of constable and its duties were distinct from those of the sheriff and jailer, Paterson, Laws (1800), pp. 203, 318, and separate reference to these positions still abound. E. g., N. J. S. 2A:151-43; N. J. S. A. 10:3-1; R. S. 30:8-1; N. J. S. A. 43 :10-18.26.
The Legislature has long recognized that the court attendant’s duties are more extensive than “preserving order in the court, taking charge of the jury, and other work incidental to the trial of cases.” 74 N. J. Super., at pp. 13A-135. In statements appended to bills enacted to regulate the fees of court attendants, it was noted that “In addition to their duties as attendants in the courts, they are used by the sheriff to serve all grand jury subpoenas, summon all grand, struck and petit jurors, subpoena all witnesses needed by the State in criminal cases, to make arrests on capias after indictment, to serve the following civil writs: Summons and Complaint, Writs of Ne Exeat, Attachment, Execution, Replevin, Citation and Petition in Divorce. To summon election officers, for duty as such, and are subject to duty as watchman in attachment action. * * *” Assembly Bill No. 79 (1919) (enacted as L. 1919, c. 24). They are “subject to call at all hours in cases of strikes and riots,” Assembly Bill No. 79 (1920) (enacted as L. 1920, c. 8), and are required to “transport dangerous criminals and insane inmates to various insti*319tutions. * * * This bill will create a standard of compensation in keeping with their added duties and responsibilities.” Assembly Bill No. 200 (1947) (enacted as L. 1947, c. 244).
The issue before us involves the authority of the sheriff to transfer court attendants under the Civil Service Act. The over-all purpose of the civil service law is to secure for state, county and municipal government efficient public service in all its many functions. Borough of Park Ridge v. Salimone, 21 N. J. 28, 44 (1956); Walsh v. Department of Civil Serv., 32 N. J. Super. 39, 43 (App. Div. 1954). Efficient public service requires civil administrators, like defendant sheriff, to make comprehensive use of their departments’ surplus manpower in cases of temporary need and emergency. “The welfare of the people as a whole, and not specifically or exclusively the welfare of the civil servant, is the basic policy underlying the law * * Borough of Park Ridge, supra.
R. S. 11 :l-7 provides that the Civil Service Commission may prescribe, amend and enforce rules and regulations for carrying out the above-stated object and purpose of the Civil Service Act. Pursuant thereto, the Civil Service Commission has detailed the circumstances under which temporary transfers in state and local government services can be made. Civil Service Rule 53, upon which defendant relies, provides in part:
“1. Transfers may be made as follows:
* * * * * ❖ * . *
(e) The transfer of an employee for a temporary period not to exceed six months from one class in a department, institution or organization unit, to the same or another class in another department, institution or organization unit may be made in order to bring about a better distribution of persons in the service or to effect economies or to make available from one or more central supply pools extra stenographic, clerical, messenger or other service needed for limited periods or to provide training sought by employees or required by appointing authorities. No such transfer shall be made without the consent of the appointing authorities from whose and to whose working forces such transfer is proposed and no employee shall be *320transferred or assigned as a result of such transfer to a position involving duties for which he is not qualified as indicated by his experience, training and record of service. Any employee who is unwilling to accept a transfer under these provisions shall have reasonable opportunity to be heard in his own behalf.”
The measure of the validity of Buie 53, as applied to the situation before us, is the Civil Service Act. Although this rule, however desirable, “may not tran-scend the scope of the statute, nor expand nor limit the statutory provisions,” Kaplan, The Law of Civil Service 104 (1958); Abelson’s, Inc. v. New Jersey State Board of Optometrists, 5 N. J. 412, 424 (1950), when challenged, the rule does have in its support the presumption, although rebuttable, of validity. In re Weston, 36 N. J. 258, 263 (1961).
Turning then to the Civil Service Act, we find provisions regarding transfers. Subtitle 2, entitled “State Service,” deals with transfers in a comprehensive manner by providing for absolute and periodical or occasional transfers of employees. B. S. 11 :ll-3. Subtitle 3, “Counties, Municipalities and School Districts,” also treats of transfers, but only in a limited situation, i. e., a permanent transfer of an employee, at his request, from a certain position in one office, department or institution to a similar position in another office, department or institution. B. S. 11:22-8. The argument is made that, inasmuch as B. S. 11:21-4 provides that “After the adoption of the civil service act * * * by any county * * * no person shall be * * * transferred * * * in the civil service of such county * * * in any other manner or by any means other than those prescribed by this subtitle,” county and municipal transfers are limited by B. S. 11:22-8.
We cannot so constfue B. S. 11:21-4. It has long been recognized that the Civil Service Act must be liberally construed to effectuate the basic policy underlying the law. Borough of Parle Bidge v. Salimone, supra. Although we there cautioned that a liberal policy of construction gives the court no license to disregard the clear meaning of the law, and all reasonable doubts must be resolved in favor of the *321express provisions of the statute, as between two possible constructions of a statute, “the: one should be adopted which effectuates rather than defeats the legislative purpose.” State Department of Civil Service v. Clark, 15 N. J. 334, 341 (1954). We find no reference to temporary transfers under subtitle 3, and likewise no implied prohibition against such transfers. Thus, the language of that section must be read in light of the Commission’s rule-making power as incorporating within the term “transfer” as used therein other transfers prescribed by Commission rules not inconsistent with B. S. 11:22-8.
The function of the rules promulgated by the Commission is to fill in the details for the complete operation of the law. Buie 53(1) encompasses just about every conceivable transfer situation — from transfers in the same class through transfers to another class at higher or lower maximum rate of compensation to transfers of veterans unable to perform their duties because of disability — and provides as its recurring theme the needs of and economies within the service, particularly in the paragraph dealing with temporary transfers. Thus Buie 53 not only fills in a statutory void, but is compatible with the various sections of subtitle 3 and implements the over-all purpose of the civil service law.
Although we hold that Buie 53(1) (e) authorizes defendant sheriff to transfer temporarily court attendants to “another class in a department, institution or organization unit,” his conduct is still circumscribed by those rules, consistent with efficiency in the sendee and the welfare of the people as a whole, which are also for the employee’s protection. Thus, no transfer may be made when “the person sought to be transferred * * * is not within the age limits if there are any prescribed, [or] does not possess the physical qualifications or the experience and training required for the efficient performance of the duties of the position to which transfer is sought,” Buie 53(2) (c), or when “the duties to be performed in the position to which transfer is sought require tests or qualifications essentially different from or higher than those *322required for original entrance to the test for the position from which transfer is sought.” Buie 53(2) (d). That the duties may be different but the transfer not prohibited is clear, not only from the foregoing rules, but from the fact that Buie 53(1) (e) allows temporary transfers from one class to another even though “class or class positions” is defined in Buie 64 as “a group of positions in the classified service * * * sufficiently similar in respect to the duties, responsibilities and authority thereof that the same descriptive title may be used to designate each position allocated to the class. "
We cannot say, on the record before us, that the sheriff failed to comply with the above-mentioned safeguards. Differences in the two positions have been called to our attention. Some, such as the fact .that court attendants regularly work from 9 a. m. to 4 p. m. while jail keepers work in shifts around the clock, have no bearing on the qualifications, experience or training required of the transferee, and even if working hours were relevant, the Legislature has acknowledged that court attendants “axe on duty and on call at all hours to perform the duties required of them, in addition to the actual attendance upon the courts.” Assembly Bill No. 200 (1947), supra. “All of these extra duties must be performed after court hours. * * *” Assembly Bill No. 79 (1920), supra.
Other differences are of more substance. Por example, the civil service specifications emphasize knowledge of court procedure for court attendants, and knowledge of problems encountered in work involving the rehabilitation, care and custody of prisoners for jail keepers. While the court attendant is not concerned with rehabilitation, he does have the care and custody of prisoners for temporary periods. Whether that would qualify him to serve temporarily as a jail keeper we cannot say. This presents a problem within the special competence of the Civil Service Commission.
Those differences of substance indicate to us, not that the sheriff could not have made a valid transfer, but that plaintiffs should have submitted their case to the Civil Service *323Commission (assuming, first, an adverse result in the hearing provided for by Rule 53(l)(e)) for its determination as to whether the duties of jail keeper require tests or qualifications essentially different from or higher than those required for original entrance to the test for court attendants, and if not, whether the transferees here involved possess the physical qualifications or experience and training required for the efficient performance of the duties of jail keeper. If still dissatisfied, R. R. 4:88-8 gives plaintiffs the simplest and most effective mode for judicial review of the Commission’s action.
The judgment of the Appellate Division is reversed and the matter is remanded to the trial court for the entry of a judgment in conformity herewith, without costs.