Section 8-36-301 - Eligibility(a) Any member in Group 1 shall be eligible for early service retirement upon satisfying one (1) of the following: (1) Attainment of fifty-five (55) years of age with the applicable years of creditable service as set forth in § 8-36-204; or(2) At any age less than fifty-five (55) years of age with twenty-five (25) years of creditable service; provided, that this provision shall be optional for political subdivisions participating under chapter 35 of this title.(b) Any member in Group 2 shall be eligible for early retirement upon satisfying one (1) of the following: (1) Attainment of fifty-five (55) years of age with ten (10) years of creditable service; or(2) If the member is employed by a political subdivision which has not authorized unreduced service retirement benefits pursuant to § 8-36-201(b)(1)(B), at any age with thirty (30) years of creditable service.(c) Any member in Group 3 shall be eligible for early service retirement upon attaining fifty-five (55) years of age with eight (8) years of service.Acts 1972, ch. 814, § 5; 1973, ch. 347, § 13; 1979, ch. 288, § 5; T.C.A., § 8-3908; Acts 1984, ch. 601, § 3; 1986, ch. 554, § 15; 1997 , ch. 67, § 2; 1998, ch. 1011, §§ 4, 5.