In 1924, while investigating the Teapot Dome scandal, a senate committee issued a subpoena to a witness in Ohio to appear to testify. The senate deputy sergeant-at-arms arrested him. The Supreme Court supported the arrest, stating that Congress acted within its power to gather information prior to legislating.
President Donald Trump is suing two banks to prevent them from complying with House subpoenas for his tax records. Deutsche Bank loaned him $2 billion dollars in the past 10 years.
On May 8, William Barr was declared in contempt of Congress for refusing to give the House Judiciary Committee the complete Mueller Report. However, Attorney General Barr is unlikely to arrest any member of the executive branch.
Congress has the power to issue a civil contempt citation but civil cases have taken up to four years. Many take so long that the question has become moot by the time it is decided.
The matter must be solved before Congress adjourns or it will die, and Trump will have won a reprieve until Congress convenes next fall.
Richard Bates, Baraboo