26 USC 7604 - Enforcement of summons

(a) Jurisdiction of district court 
If any person is summoned under the internal revenue laws to appear, to testify, or to produce books, papers, records, or other data, the United States district court for the district in which such person resides or is found shall have jurisdiction by appropriate process to compel such attendance, testimony, or production of books, papers, records, or other data.
(b) Enforcement 
Whenever any person summoned under section 6420 (e)(2), 6421 (g)(2), 6427 (j)(2), or 7602 neglects or refuses to obey such summons, or to produce books, papers, records, or other data, or to give testimony, as required, the Secretary may apply to the judge of the district court or to a United States magistrate judge for the district within which the person so summoned resides or is found for an attachment against him as for a contempt. It shall be the duty of the judge or magistrate judge to hear the application, and, if satisfactory proof is made, to issue an attachment, directed to some proper officer, for the arrest of such person, and upon his being brought before him to proceed to a hearing of the case; and upon such hearing the judge or the United States magistrate judge shall have power to make such order as he shall deem proper, not inconsistent with the law for the punishment of contempts, to enforce obedience to the requirements of the summons and to punish such person for his default or disobedience.
(c) Cross references 

(1) Authority to issue orders, processes, and judgments 
For authority of district courts generally to enforce the provisions of this title, see section 7402.
(2) Penalties 
For penalties applicable to violation of section 6420 (e)(2), 6421 (g)(2), 6427 (j)(2), or 7602, see section 7210.