How can Congress Subpoena foreign citizens?

Congress can issue subpoenas to foreign citizens as part of its oversight and investigative powers, but enforcement can be complex. While Congress has the authority to compel testimony and documents, it generally lacks the ability to enforce these subpoenas outside U.S. jurisdiction. Foreign citizens may be compelled to comply if they are in the U.S. at the time or if they have ties to American entities. Additionally, cooperation often depends on diplomatic negotiations or treaties between governments.