On and after the date of the enactment of the Pretrial Services Act of 1982, the Director of the Administrative Office of the United States Courts (hereinafter in this chapter referred to as the “Director”) shall, under the supervision and direction of the Judicial Conference of the United States, provide directly, or by contract or otherwise (to such extent and in such amounts as are provided in appropriation Acts), for the establishment of pretrial services in each judicial district (other than the District of Columbia). Pretrial services established under this section shall be supervised by a chief probation officer appointed under section 3654 of this title or by a chief pretrial services officer selected under subsection (c) of this section.