Mr Starr led the investigation into Bill Clinton in the late 1990s while Dershowitz has defended such controversial public figures as OJ Simpson, Jeffrey Epstein and Harvey Weinstein.
During the Clinton impeachment, then-private citizen Trump called Mr Starr a "freak" and a "lunatic" in his pursuit of impeaching then-president Clinton, who Mr Trump supported at the time.
As the Senate swore in chief justice John Roberts on Thursday to preside over the trial, Mr Trump responded angrily from the Oval Office, declaring he had been impeached for “absolutely no reason”.
The president has also continued to deny knowing Lev Parnas, the business associate of his attorney Rudy Giuliani who is the latest to come forward with evidence against him, placing renewed pressure on the likes of Vice President Mike Pence, Secretary of State Mike Pompeo and ex-Energy Secretary Rick Perry to reveal what they know about the Kiev plot.
But the president enjoyed a sympathetic Republican audience as he celebrated college football champions from LSU on Friday, when he joked about his impeachment while citing a strong economy and well-funded military before flying to Mar-a-Lago for the weekend.
He told the team: "They're trying t impeach the son of a b****. Can you believe that? We got the greatest economy we ever had ... We got the greatest military. We rebuilt it. We took out those terrorists like your football team would've taken out those terrorists, right?"
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