The lawyers for porn star Stormy Daniels and other women accusing President Donald Trump of sexual improprieties are aiming to catch him lying under oath, Harvard Law professor emeritus Alan Dershowitz said Wednesday.
"Under no circumstances can he [Trump] testify about his relations, or lack of relations, with these women," Dershowitz told Fox News' "America's Newsroom" co-host Bill Hemmer.
Daniels' attorney Michael Avenatti has requested in federal court to take a deposition from Trump in the legal battle over an agreement to keep her quiet about her allegation they had a sexual relationship.
He also wants to depose Trump's lawyer, Michael Cohen, who Daniels is suing for defamation, according to a motion filed in United States District Court in the Central District of California.
Former Playboy model Karen McDougal has claimed to have had a 10-month affair with Trump starting in 2006, while he was married to his current wife, Melania. The White House has denied both claims, but Trump has not addressed the allegations publicly.
A former guest on Trump's reality show, "The Apprentice," also has accused Trump of improprieties.
"The end game is very simple; to get President Trump under oath and get him into a he said, she said swearing contest with one of these, or both of these, or three of these women," Dershowitz said. "That's how they got Bill Clinton. They turned Whitewater into the blue dress and got him impeached based on perjury."
Dershowitz said he does not think Trump is vulnerable to special counsel Robert Mueller on charges of obstruction of justice or Russian collusion, but the matter of Stormy Daniels is different.
"If he testifies under oath, and he denies having had relationships with these women, and these women persist and one of them comes up with the analog to a blue dress, then he has a perjury charge," said Dershowitz, making a second reference to the infamous blue dress worn by Clinton intern Monica Lewinsky during one of their encounters that ended up being used as evidence against him.
Perjury, Dershowitz said, is "one of the specifications in the Constitution for impeachment. Perjury, treason, or other high crimes and misdemeanors. One of the things that has to be a constant, under no circumstances can he testify about his relations, or lack of relations, with these women."
Trump can't refuse to testify, and he must submit to a deposition if he is sued, Dershowitz.
"If any of these women sue him, in the one case in New York, you can sue the president if one of his agents denied he had relations," Dershowitz said. "The words of the agents are attributable to the president, and he can be sued for defamation."
Trump's legal team has already made a "dreadful mistake" by trying to hire Bob Bennett, "the one who got President Clinton impeached."
"He walked him into the perjury trap and had him testify about his sex life instead of defaulting the case or settling the case," Dershowitz said.
"I strongly recommended President Clinton on the air, on this network that he either default or settle but under no circumstances should he ever have testified about his sex life. That's what got him impeached. And it was Bob Bennett, and they're trying to hire them. What's wrong with them?"
Trump's attorneys can delay his testimony, said Dershowitz, but in the end, he will be compelled either to testify or default the case against him if he is sued.
"I hope he has good enough lawyers to tell him, please, default," Dershowitz said. "Do not testify under any circumstances. Don't walk into a perjury trap. If you do, that is a ground for impeachment."
Dershowitz said he also thinks Trump needs a well-rounded team of lawyers to fight his case, and said he ought to be able to assemble a team.
Dershowitz said "you have to worry about" the judgment of whoever advised Trump to try to hire Bennett.
Trump "needs a team that includes experienced constitutional criminal lawyers and needs a team that includes people who negotiate with Mueller," Dershowitz added. "He has some of that team in place but I think he needs to enhance the team."