Section 28A(5) in The Rajasthan Police Service Rules, 1954
(5)Subject to the provisions of sub-rule (7), selection for promotion from the lowest post or category of post in the State Service to the next higher post or category of post in the State Service and for all posts in the Subordinate Services and in the Ministerial Services shall be made strictly on the basis of seniority-cum-merit from amongst the persons who have passed the qualifying examination, if any, prescribed under these Rules, and have put in at least five years service, unless a different period is prescribed elsewhere in these Rules, on the first day of the month of April of the year of selection on the post or category of post from which selection is to be made:Provided that in the event of non-availability of the persons with the requisite period of service of five years, the Committee may consider the persons having less than the prescribed period of service, if they fulfill the qualifications and other conditions for promotion prescribed elsewhere in these Rules, and are found otherwise suitable for promotion on the basis of seniority-cum-merit.