Dershowitz Doubts Trump Will Pardon Manafort: 'I Don't See Any Light at the End of the Tunnel'

President Donald Trump is unlikely to pardon his former campaign chairman Paul Manafort because the political costs would be too high, said Harvard law professor Alan Dershowitz.

And Manafort—who was convicted of multiple counts of fraud and pleaded guilty to other federal charges of conspiracy against the U.S. and obstruction of justice—would likely serve a long prison term, Dershowitz said.

Manafort was accused of breaking his plea agreement with the Department of Justice by lying to the FBI and the office of special counsel Robert Mueller, who is leading the Russia investigation.

Some have speculated that Manafort, who said he spoke truthfully to investigators, was eyeing a presidential pardon. Otherwise, he could end up spending the rest of his life behind bars.

There is a joint defense agreement in place between the legal teams of Manafort and the president, who has not ruled out pardoning his former associate. The two camps were in communication even after Manafort signed the plea deal.

"I can't imagine what incentive Trump would have to incur the political costs of granting a pardon when Manafort has been neutralized as a witness," constitutional and criminal law scholar Dershowitz told Newsweek .

"He has become, in many respects, an irrelevancy to the case. So it's hard for me to see any reason why the president would grant a pardon unless he felt strongly about the injustice that he feels may have been imposed on Manafort. But it's not a particularly sympathetic case for a pardon at this point.

"I think he's going to get a long prison term and will probably have to serve it. I don't see any light at the end of the tunnel for him unless there are things we don't know.

"But, right now, the first rule is when you make a deal to cooperate, which is something I almost never do because it gives too much power to prosecutors, but if you're going to make a deal to cooperate you have to be willing to do it 110 percent. You can't just do it part of the way."

Manafort may still play a cooperating role in the special counsel's probe, which is investigating Russian interference in the 2016 presidential election, and possible cooperation between the Trump campaign and the Kremlin.

The special counsel, however, "would never use Manafort as a witness because any defense attorney could rip him apart," Dershowitz told Newsweek.

"But he might still use his information in a report because there's no cross-examination. That's the vice of a prosecutorial report. It's one sided, and there's no opportunity to challenge what's in it unless the other side is given an opportunity to respond contemporaneously."