Washington (CNN) Supreme Court Justice nominee Brett Kavanaugh, while working on the independent counsel investigation into President Bill Clinton in 1995, argued that a sitting president would likely have to testify before a grand jury if subpoenaed.

Kavanaugh, who worked for independent counsel Ken Starr at the time, asked in a memo whether "there could be some kind of argument based on the 'dignity of the Presidency' and/or separation of powers" protecting the disclosure of then-President Clinton and first lady Hillary Clinton's testimonies under grand jury secrecy rules.

Kavanaugh calls that argument "weak" in the memo to Starr and other members of the independent counsel team on January 25, 1995.

"This argument seems weak, however, given the deeply rooted history and tradition of this country's jurisprudence that the President is not above the law," he said, later asking, "Why should the President be different than anyone else for purposes of responding to a grand jury subpoena ad testificandum?"

Kavanaugh, currently a federal appeals judge, also contends in the memo that "once in the grand jury room, the President might claim executive privilege if asked about certain communications, but that seems a different issue altogether."

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