CHICAGO (CBS/CNN) — Illinois U.S. Rep. Mike Quigley questioned former special counsel Robert Mueller Wednesday at the second of two Congressional hearings on his report into Russian interference in the 2016 presidential election.

Quigley (D-5th) asked Mueller what would happen if a president, who cannot be indicted while seated but can be once they leave office, serves longer than the statute of limitation. Mueller said he wasn’t sure.

Here is part of the exchange:

Quigley: “Thank you for being here. Earlier today, and throughout the day, have you stated the policy that a seated president cannot be indicted, correct?”

Mueller: Right.

Quigley: And upon questioning this morning, you were asked that could a president be indicted after their service, correct?

Mueller: Yes.

Quigley: The follow-up question that should be concerning is, what if a president serves beyond the statute of limitations?

Mueller: I don’t know the answer to that one.

Mueller has testified that a U.S. president could be charged after he or she leaves office. He has not, however, said if Trump should be prosecuted after he leaves office.

Democratic Rep. Mike Quigley also read several quotes that President Trump said about WikiLeaks, including “This WikiLeaks is like a treasure trove” and “Boy, I love reading those WikiLeaks.” The comments were Trump’s reaction to leaked information on Hillary Clinton’s campaign.

Quigley asked Mueller to react to those lines.

“Problematic is an understatement in terms of what it displays in terms of giving some hope or some boost to what is and should be illegal activity,” Mueller said.

Mueller said Russia’s interference in the 2016 presidential election was “not a hoax.”

His remarks on Russian interference came during a line of questioning by Rep. Jackie Speier (D-CA, 14th), who described it as “an invasion” as well as “sinister and scheming.”

Asked if he would agree that it was not a hoax and that the Russians were engaged in trying to impact the U.S. election, Mueller said, “Absolutely, it was not a hoax.”

“The indictments we returned against the Russians — two different ones — were substantial in their scope, using the scope word again. And I think we have underplayed to a certain extent that aspect of our investigation that has and would have long term damage to the United States that we need to move quickly to address.”

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