12 U.S.C. § 484 : US Code - Section 484: Limitation on visitorial powers

      (a) No national bank shall be subject to any visitorial powers
    except as authorized by Federal law, vested in the courts of
    justice or such as shall be, or have been exercised or directed by
    Congress or by either House thereof or by any committee of Congress
    or of either House duly authorized.
      (b) Notwithstanding subsection (a) of this section, lawfully
    authorized State auditors and examiners may, at reasonable times
    and upon reasonable notice to a bank, review its records solely to
    ensure compliance with applicable State unclaimed property or
    escheat laws upon reasonable cause to believe that the bank has
    failed to comply with such laws.