(1) After July 1, 1974, a sheriff may not become a member of the public employees' retirement system and the provisions of The Public Employees' Retirement System Act do not apply to sheriffs.
(2) After July 1, 1993, an investigator is not eligible to become a member of the public employees' retirement system and the provisions of The Public Employees' Retirement System Act do not apply to investigators, except as provided in 19-7-301.
(3) After July 1, 2005, a detention officer is not eligible to become a member of the public employees' retirement system and the provisions of The Public Employees' Retirement System Act do not apply to detention officers, except as provided in 19-7-301.
(4) This chapter may not be construed to deny any sheriff, investigator, or detention officer any benefits accrued under provisions of the public employees' retirement system prior to membership in this retirement system.