There have been reports that the FBI sought approval last summer to monitor members of the Trump team suspected of having irregular talks with the Russians. Ali Soufan, chair of the Soufan Group security firm and a former FBI agent, noted that such requests must be sanctioned by federal judges.
“The president cannot order criminal wiretaps or any other kind of wiretaps,” said Soufan. “No president can."
The process for obtaining a federal wiretap, either for domestic crimes or for foreign intelligence purposes, involves the approval and supervision of a federal judge. Those requests are made by investigators themselves, and the president is ultimately briefed on them only if Justice Department officials believe it is necessary.
“They deliberately withhold that because they don't want the president to get involved in an ongoing investigation," said Clint Watts, a fellow at the Foreign Policy Research Institute and a former FBI special agent. "They play by a really strict rulebook at DoJ."
Bruce Green, a law professor at Fordham and a former federal prosecutor said a president ordering a wiretap would be unusual, to say the least.
“It would obviously be improper for the government to seek wiretap authorization for partisan political purposes, rather than legitimate criminal investigative or national security purposes as set out in the application to the court,” said Green. “In prior administrations, if a President directed the Attorney General or another government lawyer to seek wiretap authorization for illegitimate reasons, the lawyer would have been expected to try to dissuade the President and, if the President persisted in giving this order, to refuse and/or resign.”
A judge would also likely refuse such a request. “An ethical government lawyer would be expected to disclose the President's involvement to the court, which could then be expected to deny authorization,” Green said.
If, hypothetically, a judge did approve a warrant for electronic surveillance of Trump officials, that would mean the judge was persuaded there was probable cause to believe they were going to commit a crime or were communicating with agents of a foreign power––and that the gravity of the circumstances justified approving the request, even in the face of the massive potential political fallout.
Reports have also suggested that former National Security Adviser Mike Flynn’s conversations with the Russian Ambassador Sergey Kislyak were picked up during surveillance of Kislyak. The FBI sometimes eavesdrops on foreign leaders while in the U.S., and it is possible that agents overheard Flynn’s conversation while monitoring Kislyak’s phone line. Flynn ultimately resigned, after it was reported that he misled administration officials about the content of his conversations with Kislyak.