https://thinkprogress.org/1998-rudy-giuliani-debunked-2018-rudy-giuliani-on-presidents-evading-subpoenas-5e14e567f6c7/
"Rudy Giuliani claimed over the weekend that the president of the United States need not comply with a subpoena to testify if he is called by Special Counsel Robert Mueller. But this dubious legal argument was clearly rebutted, back in 1998, by then-New York City Mayor Rudy Giuliani."
