Transcript for Mounting questions about whether Trump's lawyer will flip on president

Meantime, speculation growing in tin vest game of president trump's personal attorney, Michael Cohen, after the sweeping raids by the FBI. Prosecutors say they are focusing on Cohen's personal business dealings. "The New York Times" reporting that Cohen could flip. The president reacting to that report, and tonight what we've learned right here. Here's ABC's sere are Phillips. Reporter: Tonight, mounting questions about whether the man known for his pledge of loyalty -- I will do anything to protect Mr. Trump. Reporter: -- Could flip on his most famous client. The president's long-time personal attorney, Michael Cohen, is under criminal investigation. The feds seized evidence from his home, office and hotel. Including documents related to alleged hush money payments to protect Donald Trump's image. "The New York Times" reporting Cohen, now under intense pressure, could turn on the president, prompting the president to tweet that's not like Cohen, saying, "Most people will flip in the government lets them out of trouble, even if it means lying or making up stories." Sorry, I don't see Michael doing that despite the horrible witch hunt." Reporter: But Cohen could ultimately face jail time. This is an epic battle for the soul and cooperation of Michael Cohen. And prosecutors have enormous weapons at their disposal. Reporter: The president also tweeting about a potential pardon of someone else, which left some people to speculate he was trying to send a message to Cohen. Tonight, the white house saying they're not ruling out a presidential pardon. The president open to a paradob for Michael Cohen? Ah, I don't think we're going to talk about hypotheticals that don't exist right now. Reporter: When pressed later -- It's hard to close a door on something that hasn't taken place. Let's get to Kyra Phillips, with us from Washington tonight. And a lot of speculation over what Michael Cohen might or might not do, as this investigation intensifies. Reporter: David, tonight, a source close to Cohen telling ABC news Michael Cohen will never flip, calling it pure speculation, as Cohen continues to be tried in the court of public opinion. But if Cohen ever faces jail time, his deep access to trump's personal and financial dealings may lead prosecutors to offer him a deal he just can't refuse. David? Kyra Phillips with us again tonight.

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