; (B) a criminal investigator classified under the GS–1811 series (or any successor series); (C) a Federal air marshal; (D) a special agent in the Diplomatic Security Service; (E) a probation officer (referred to in section 3672 of title 18); and (F) a pretrial services officer (referred to in section 3153 of title 18). . (b) Conforming amendment Section 410(b)(11) of title 39, United States Code, is amended by striking section 5520a and inserting sections 5520a and 5545a . 4. Credit for certain lump-sum payments of uncompensated law enforcement premium pay (a) In general In the case of an individual, there shall be allowed as a credit against the tax imposed by chapter 1 of the Internal Revenue Code of 1986 for the taxable year an amount equal to the sum of the lump-sum payments made by the individual during such taxable year pursuant to section 8339(v)(2) or 8415(o)(2) of title 5, United States Code, with respect to an annuity of such individual. (b) Treated as non-Refundable personal credit For purposes of the Internal Revenue Code of 1986, the credit allowed under subsection (a) shall be treated as a credit allowed under subpart A of part IV of subchapter A of chapter 1 of such Code.