Alan Dershowitz said Special Counsel Robert Mueller is "squeezing" former Trump campaign chairman Paul Manafort to get to President Trump.

Mueller's team on Tuesday requested that a court compel "five potential witnesses" to testify at one of Manafort's upcoming trials in exchange for immunity, FoxNews.com reported.

Manafort faces numerous charges, including conspiracy to commit money laundering, making false statements and working as an unregistered agent of the government of Ukraine. If convicted, he faces decades in prison.

On "America's Newsroom," Dershowitz, a Harvard Law professor emeritus, noted that Manafort was indicted for matters unrelated to Russian meddling in the 2016 election.

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He said it's clear that Mueller's team is targeting Trump and the people around him, and they're attempting to use Manafort to do so.

"He's a means toward the end. And that's just not the way justice should operate," Dershowitz said. "Civil libertarians have long been opposed of that method of squeezing witnesses -- indicting them for kind of unrelated crimes and then trying to get them to testify against more important people."

He added that a concern is that not only will Manafort "sing," he will "compose," meaning that he might make things up or exaggerate because the better story he tells, the better deal he will get.

Manafort's trial before Washington, D.C., District Court Judge Amy Berman Jackson is expected to take place in September.

Watch more from Dershowitz above.

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