Where appropriate, the provisions of part
II of title
18 and of title 28 and, notwithstanding the provisions of rule 7(a) and of rule
54(a) of the Federal Rules of Criminal Procedure relating to the requirement of indictment and to the prosecution of criminal offenses in the Virgin Islands by information, respectively, the rules of practice heretofore or hereafter promulgated and made effective by the Congress or the Supreme Court of the United States pursuant to titles 11, 18, and 28 shall apply to the district court and appeals therefrom: Provided, That the terms “Attorney for the government” and “United States attorney” as used in the Federal Rules of Criminal Procedure, shall, when applicable to causes arising under the income tax laws applicable to the Virgin Islands, mean the Attorney General of the Virgin Islands or such other person or persons as may be authorized by the laws of the Virgin Islands to act therein: Provided further, That in the district court all criminal prosecutions under the laws of the United States, under local law under section
1612
(c) of this title, and under the income tax laws applicable to the Virgin Islands may be had by indictment by grand jury or by information: Provided further, That an offense which has been investigated by or presented to a grand jury may be prosecuted by information only by leave of court or with the consent of the defendant. All criminal prosecutions arising under local law which are tried in the district court pursuant to section
1612
(b) of this title shall continue to be had by information, except such as may be required by the local law to be prosecuted by indictment by grand jury.