Tenn. Code § 17-525
Disability means a physical or mental condition of a member which has persisted for six (6) months, which is likely to be permanent, and which has rendered him incapable of further performance of his duties; provided, however, that the event or illness which is deemed by the board to have resulted in the disability had its origin during the time the member was an actively employed judge. Loss of both hands by severance at or above the wrists, or both feet at or above the ankles, or the complete irrecoverable loss of the sight of both eyes, shall conclusively determine disability. Notwithstanding any provision of this section to the contrary, disability as defined in this section shall not include a physical or mental condition which results directly or indirectly from:
The retirement board shall have exclusive authority to determine the existence of disability. The board, in its sole discretion, may secure such medical and other evidence as it deems necessary and appropriate. Once each calendar year, the board may require any retired member who is receiving a disability benefit and who has not reached his normal retirement date to undergo a medical examination by a physician or physicians designated by the board, and such examination shall be made at the place of residence of such retired member or at any other place the retirement board designates. If a retired member refuses to submit to such medical examination, his disability benefit shall be discontinued until he shall actually undergo such medical examination; and if he fails to undergo such medical examination for one (1) year from the date the retirement board requests such medical examination, his disability benefit shall be discontinued permanently. If the board determines that he is no longer disabled, his disability benefit shall be discontinued as of the date of such determination; provided, however, that if the retired member reapplies for disability benefits and the board determines that disability exists, payment of his disability benefit shall resume as of the date of such determination that disability exists. If the disability benefit of a retired member is discontinued permanently prior to his normal retirement date and he is reemployed as a judge by the employer within six (6) months following the date his disability ceases, his credited service shall not be deemed to have been interrupted, but shall not include any time during which he was not an employee.
T.C.A. § 17-525