After plea deals, what is Trump's legal exposure?

Tuesday was a bad day in court for former associates of President Donald Trump, and it could foreshadow hard days ahead for the president. What do the developments mean for the president?

Trump's lawyers have been negotiating with Robert Mueller about whether the president would submit to an interview as part of Mueller's Russia investigation. Now porn actress Stormy Daniels' attorney Michael Avenatti says he'll renew efforts to get Trump to submit to a deposition in a lawsuit Daniels filed to invalidate a nondisclosure agreement she signed ahead of the 2016 election.

Avenatti tweeted the Michael Cohen pleas should "permit us to proceed with an expedited deposition of Trump under oath about what he knew, when he knew it, and what he did about it."

The Supreme Court in 1997, ruling in a sexual harassment lawsuit brought by Paula Jones against President Bill Clinton, held a sitting president could be made to answer questions as part of a civil lawsuit. But that ruling did not directly address whether a president could be subpoenaed to testify in a criminal investigation, a question the Supreme Court may have to confront if Mueller tries to compel Trump's testimony in his probe.

IF THERE IS EVIDENCE OF WRONGDOING, CAN TRUMP BE INDICTED?

The Justice Department's Office of Legal Counsel, which provides legal advice and guidance to executive branch agencies, has held a sitting president cannot be indicted.

Trump's lawyers have said Mueller plans to adhere to that guidance, though Mueller's office has never independently confirmed that. There would presumably be no bar against charging a president after he or she leaves the White House.

Sol Wisenberg, who conducted grand jury questioning of Clinton as deputy independent counsel during the Whitewater investigation, said he still wanted to see more details of Cohen's plea deal, but said "obviously it's not good for Trump. The stuff on Stormy Daniels is not good for Trump."

"I'm assuming he's not going to be indicted because he's a sitting president," said Wisenberg. "But it leads him closer to ultimate impeachment proceedings, particularly if the Democrats take back the House."

HOW DOES COHEN'S PLEA RELATE TO THE MUELLER INVESTIGATION?

While the Manafort case was part of Mueller's investigation, the Cohen case was not. It was handled by prosecutors in New York. Still, it could give Mueller a boost.

Laurie Levenson, a former federal prosecutor and professor at Loyola Law School in Los Angeles, argued Cohen's plea knocks back the argument the investigations swirling around Trump are a "witch hunt," as the president has called Mueller's Russia investigation.

"No longer can you say Mueller is on a witch hunt when you have his own lawyer pleading guilty to things that were designed to impact the election," she said.

COULD TRUMP PARDON HIMSELF?

Trump has already shown he's not afraid to use his pardon power, particularly for those he has viewed as unfair victims of partisanship. He pardoned Joe Arpaio, the former Arizona sheriff who clashed with a judge on immigration, and I. Lewis "Scooter" Libby, a Bush administration official convicted of perjury and obstruction of justice in a leak case.

As for whether a president can pardon himself, not surprisingly, courts have never had to answer that question. Giuliani, Trump's lawyer, has said it won't come to that anyway.

"Pardoning himself would be unthinkable and probably lead to immediate impeachment," Giuliani told NBC's "Meet the Press" in June. And he has no need to do it, he's done nothing wrong." Still, Giuliani argued Trump "probably does" have the power to pardon himself.