((a)) ** .—** A judicial officer authorized to order the arrest of a person under before whom an arrested person is brought shall order that such person be released or detained, pending judicial proceedings, under this chapter.

((b)) ** .—** A judicial officer of a court of original jurisdiction over an offense, or a judicial officer of a Federal appellate court, shall order that, pending imposition or execution of sentence, or pending appeal of conviction or sentence, a person be released or detained under this chapter.