WASHINGTON – If President Trump thinks the Supreme Court can rescue him from impeachment, he should check with his latest nominee there, Brett Kavanaugh.

The new associate justice, who two decades ago was among President Bill Clinton's pursuers at the Justice Department, has written that impeachment is the sole province of Congress.

"If the president does something dastardly, the impeachment process is available," Kavanaugh wrote in a 2009 law review article. "No single prosecutor, judge or jury should be able to accomplish what the Constitution assigns to the Congress."

To drive home the point, Kavanaugh – a federal appeals court judge at the time – cited Article I, Section 3, Clause 6, which empowers the Senate in impeachment trials. The next clause makes clear an impeached president can later be indicted and convicted.

Trump threatened Wednesday to involve the high court if Democrats try to impeach him over special counsel Robert Mueller's findings in the Russia investigation. He did not explain how he might do that.

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Kavanaugh's Minnesota Law Review article made the rounds during his confirmation process last year. At the time, it was cited for his endorsement of a powerful president and executive branch. He suggested that presidents should be immune from criminal investigations and prosecutions, as well as personal civil suits, until after leaving office.

"I believe it vital that the president be able to focus on his never-ending tasks with as few distractions as possible," Kavanaugh wrote.

For a primary author of independent counsel Kenneth Starr's occasionally explicit report detailing Clinton's transgressions with Monica Lewinsky, Kavanaugh traveled a long way to recommending that presidents be free from prosecution.

"This is not something I necessarily thought in the 1980s or 1990s," he wrote. But "looking back to the late 1990s, for example, the nation certainly would have been better off if President Clinton could have focused on Osama bin Laden without being distracted by the Paula Jones sexual harassment case and its criminal-investigation offshoots."

Kavanaugh did not suggest that judges treat presidents differently, however. He said Congress should pass a law providing that civil suits and criminal investigations be deferred while the president is in office.