28 U.S. Code § 2250 - Indigent petitioner entitled to documents without cost
If on any application for a writ of habeas corpus an order has been made permitting the petitioner to prosecute the application in forma pauperis, the clerk of any court of the United States shall furnish to the petitioner without cost certified copies of such documents or parts of the record on file in his office as may be required by order of the judge before whom the application is pending.
Derived from H.R. 4232, Seventy-ninth Congress, first session. It conforms to the prevailing practice.