1. Any Tier I member may retire when such member has completed twenty-five or more years of creditable service. Upon such retirement such member shall receive a base pension equal to:

(1) For a member retiring prior to August 28, 2000, two percent of such member’s final compensation, as defined in section 86.900, multiplied by the number of years of such member’s total creditable service; or

(2) For a member retiring on or after August 28, 2000, and prior to August 28, 2013, two and one-half percent of such member’s final compensation, as defined in section 86.900, multiplied by the number of years of such member’s total creditable service. Such pension shall not exceed seventy-five percent of the member’s final compensation; or

(3) For a member retiring on or after August 28, 2013, two and one-half percent of such member’s final compensation, as defined in section 86.900, multiplied by the number of years of such member’s total creditable service. Such pension shall not exceed eighty percent of the member’s final compensation.

2. Any Tier I member in service who shall have attained sixty years of age and at that time shall have completed at least ten years of creditable service may retire and upon such retirement shall receive a base pension equal to:

(1) For a member retiring prior to August 28, 2000, two percent of such member’s final compensation, as defined in section 86.900, multiplied by the number of years of such member’s total creditable service; or

(2) For a member retiring on or after August 28, 2000, two and one-half percent of such member’s final compensation as defined in section 86.900 multiplied by the number of years of such member’s total creditable service.

3. Subject to the provisions of subsection 4 of this section, whenever the service of a Tier I member is terminated for any reason prior to death or retirement and the member has fifteen or more years of creditable service, the member may elect not to withdraw such member’s accumulated contributions and shall become entitled to a base pension commencing on the first day of the month following the attainment of the age of fifty-five, if then living, equal to:

(1) For a member whose service so terminates prior to August 28, 2001, two percent of such member’s final compensation multiplied by the number of years of such member’s creditable service; or

(2) For a member whose service so terminates on or after August 28, 2001, two and one-half percent of such member’s final compensation multiplied by the number of years of such member’s creditable service.

4. Notwithstanding any other provisions of sections 86.900 to 86.1280, any member who is convicted of a felony prior to separation from active service shall not be entitled to any benefit from this retirement system except the return of such member’s accumulated contributions.