Sec. 5.05. MEDICAL REEXAMINATION AND REDUCTION OF DISABILITY RETIREMENT BENEFITS. (a) The board may cause a disability retiree to undergo a medical examination or examinations by any reputable physician or physicians selected by the board.

(a-1) A disability retiree who is awarded a catastrophic injury disability annuity under Section 5.03(a-1) of this Act shall undergo a medical examination by any reputable physician or physicians selected by the board:

(1) not later than 60 months after the date of the award of the annuity by the board; and

(2) thereafter, not later than 60 months following the last required medical examination of the disability retiree under this subsection.

(a-2) The board may require one or more medical examinations under Subsection (a) of this section in addition to those required under Subsection (a-1) of this section.

(a-3) Subject to Subsection (c) of this section, based on an examination under Subsections (a), (a-1), or (a-2) of this section, the board shall determine whether the disability retirement annuity shall be continued, decreased, restored to the original amount if it had been decreased, or discontinued.

(b) For those retired because of disability before August 30, 1971, the board may change the disability retirement annuity provided by this Act, in accordance with any change in the degree of disability, except that the percentage used to compute the annuity may not, except in the case of discontinuance, be reduced to less than 2.25 percent of the base pay of a private each month, for each year that the retiree has served and contributed a portion of salary as provided by this Act, based on the greater of:

(1) the rate of pay at the time of the original granting of the disability retirement annuity; or

(2) a minimum base pay of $200 each month.

(c) For those retired because of disability on or after August 30, 1971, the disability retirement annuity may not be reduced to an amount that is less than the product of:

(1) 2.25 percent multiplied by the number of years that the retiree served in the department and contributed a portion of salary as a member of the fund multiplied by the retiree's average total salary, if the retiree served three years or more before the date of retirement;

(2) 2.25 percent multiplied by the number of years that the retiree served in the department and contributed a portion of salary as a member of the fund multiplied by the retiree's average monthly salary as of the date of retirement multiplied by 12, if the retiree served at least two months and less than three years before the date of retirement; or

(3) 2.25 percent multiplied by the number of years that the retiree served in the department and contributed a portion of salary as a member of the fund multiplied by the retiree's average daily salary as of the date of retirement multiplied by 360, if the member has served less than two months before the date of retirement.

(c-1) In making the computation under Subsection (c) of this section, all fractional years shall be prorated based on full months served in the department as a contributing member of the fund before the date of retirement.

(d) If a disability retiree, after notice, fails to undergo a medical examination as provided by this section, the board may reduce or entirely discontinue the retiree's disability annuity payments.