WASHINGTON (AP) — President Donald Trump’s new attorney, Rudy Giuliani, is off to a rough start in his media blitz defending Trump’s stance toward the special counsel’s Russian investigation and a $130,000 porn star hush payment.

Giuliani’s confounding and at times contradictory statements are said to have pleased Trump, exasperated White House aides and attorneys and worried the president’s allies.

Alan Dershowitz, a Harvard law professor who has informally counseled the president, said Sunday recent developments are aiding the efforts of special counsel Robert Mueller, who is investigating contacts between the Trump 2016 campaign and Russia, as well as possible obstruction of justice.

“It seems to me that the approach last week of the Trump team plays into the hands of Mueller’s tactic to try, at any cost, to try to find technical violations against lower-ranking people so that they can be squeezed,” said Dershowitz.

In an interview Sunday with ABC’s “This Week,” Giuliani dismissed as rumor his own statements about Trump’s payment to adult-film actress Stormy Daniels, said he can’t speak to whether the president lied to the American people when he denied knowledge of the silencing agreement and wouldn’t rule out the president asserting his Fifth Amendment right against self-incrimination in the Russia investigation. Giuliani also couldn’t say whether Trump’s personal lawyer, Michael Cohen, had made similar payments to other women on the president’s behalf.

Giuliani, a former federal prosecutor, said despite Trump’s openness to sit down with Mueller in the Russia investigation, he would strongly advise Trump against it.

“I’m going to walk him into a prosecution for perjury like Martha Stewart?” Giuliani asked, referring to the lifestyle maven convicted in 2004 of lying to investigators and obstruction in an insider trading case.

Giuliani couldn’t guarantee Trump wouldn’t end up asserting his constitutional right to refuse to answer any questions that might incriminate him.

“How could I ever be confident of that?” Giuliani said.

During a 2016 campaign rally, Trump disparaged staffers of his Democratic opponent, Hillary Clinton, for taking the Fifth Amendment during a congressional investigation into Clinton’s use of a private email server as secretary of state.

“The mob takes the Fifth,” Trump said. “If you’re innocent, why are you taking the Fifth Amendment?”

Giuliani also suggested Trump wouldn’t necessarily comply with a subpoena from Mueller, whose investigation Trump has repeatedly labeled a “witch hunt.”

A subpoena fight would likely find its way to the Supreme Court, which has never firmly decided whether presidents can be compelled to speak under oath.

Giuliani, hired by Trump last month, said he’s still learning the facts of the Mueller case and the details of Trump’s knowledge of the payment to Daniels, who has alleged a sexual tryst with Trump in 2006. The $130,000 payment was made by Cohen days before the 2016 election, raising questions of compliance with campaign finance and ethics laws.