La. Stat. tit. 33 § 2531
Permanent appointments and promotions for paid firemen and policemen in the classified civil service as enumerated herein in all municipalities having a population of not less than seven thousand and not more than thirteen thousand, according to the last preceding decennial census of the United States for which the final report of population returns have been printed, published and distributed by the director of the census or according to a special census authorized by R.S. 1:11.1 subject to the approval of the local governing authority and verified by the state treasurer if said special census is later, and in all parishes and fire protection districts, shall be made only after certification pursuant to a general system based upon merit, efficiency and fitness, under which certificates shall be based on examinations which, so far as practical, shall be competitive, and all employees in the classified service shall be employed from those eligible under such certification.
La. R.S. § 33:2531