'F*** the Law!': CUNY Law School Students Disrupt Professor's Lecture on Free Speech

Former Solicitor General Kenneth Starr said Thursday that the investigation into President Trump's personal attorney is "very troubling."

"Any time that a lawyer's office is raided, I believe all Americans should be concerned about that," said Starr, who investigated then-President Bill Clinton as independent counsel in the 1990s.

FBI agents raided Cohen's home, hotel room and offices last week, reportedly obtaining documents related to Cohen's payment to adult film star Stormy Daniels, who alleges she had an affair with Trump in 2006.

"I'm very concerned about the process that's going to be followed to protect the attorney-client privilege, which is sacrosanct in American law, and it should be," Starr said.

Cohen's attorneys said in a letter to a federal judge that attorney-client privilege is not being protected, as the documents seized were about Cohen's clients and did not have to do with the president.

They wrote in the letter, in part, “A special master should be appointed in the interest of the administration of justice to ensure that the Government does not have access to materials for which they have not yet shown would be obtained through a valid search warrant through a showing of probable cause."

Starr said that people should be concerned about the process going forward in Cohen's case, and to make sure that process is carried out "with great care and sensitivity to individual liberty."

Deputy Attorney General Rod Rosenstein, who signed off on the Cohen raid, told Trump he is not a target of the Cohen investigation.

Watch more from "The Story with Martha MacCallum" and read more about the investigation into Michael Cohen.

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