(a) Except as provided in subsections (a-1) and (b) of this section, the annual rates of basic compensation of the officers and members of the Metropolitan Police force and the Fire Department of the District of Columbia shall be fixed in accordance with the following schedule of rates:
(a-1) The Chief of Police, effective January 2, 2007, and the Fire Chief, effective April 16, 2007, shall be paid in accordance with the DX Schedule for subordinate agency heads pursuant to § 1-610.52.
(b) Compensation may not be paid, by reason of any provision of this subchapter, at a rate in excess of the rate of basic pay for level V of the Executive Schedule contained in subchapter II of Chapter 53 of Title 5, United States Code.
(c) Notwithstanding any other law or regulation, the annual rates of basic compensation of officers appointed pursuant to § 1-610.72 shall be established by the salary schedule established in subsection (a) of this section as modified pursuant to § 5-545.06a.