La. Consolidated Public Retirement § 11:1112
All persons who become employees after December 31, 1946, may become members of the retirement system provided that within one year from the date of their employment they file with the board of trustees on a form prescribed by it a notice of their election to be covered in the membership of the system, together with their enrollment as a member, executed on a form prescribed by the board. Any such employee who fails to file notice of his election and his enrollment may become a member of the system at any future date, but he shall not be entitled to any prior service credit. Any employee who has failed to file this notice prior to July 28, 1948, but who does so within sixty days thereafter shall be privileged to become a member and as such shall be entitled to prior service credit.
La. Consolidated Public Retirement § 11:1112