On Monday, conservative commentator Jerome Corsi said he planned to turn down a plea agreement offered by Special Counsel Robert Mueller, and Mueller's office said in a court filing that it's scrapping its plea agreement with President Trump's former campaign chairman Paul Manafort because he'd lied to investigators and committed additional federal crimes after signing his plea deal in August.

This is bad news for Mueller, who potentially loses two witnesses, but it also means possible life in prison for Manafort and an indictment for Corsi, a key ally of longtime Trump associate Roger Stone. So why are Manafort and Corsi bucking Mueller?

On MSNBC, former vice presidential chief of staff Ron Klein and former federal prosecutors Harry Litman and Mimi Rocha suggested Manafort was either acting extremely irrationally or had reason to believe Trump would pardon him, and Rocha agreed it's "definitely possible" Manafort found life in prison preferable to crossing Russian President Vladimir Putin.

Later on MSNBC, former federal prosecutor Daniel Goldman noted "we don't have any evidence" Manafort was "dangled a pardon" or is afraid of Russian hit squads, suggesting to Ali Velshi that Manafort is simply "self-interested and irrational" and may have been "unwilling to admit to additional crimes, perhaps related to the campaign and Russia." Fellow former federal prosecutor Barbara McQuade guessed Corsi wasn't cooperating because Mueller wouldn't agree to "a promise of probation or some other sweetheart deal" and he thinks he can somehow still avoid jail time.

At Fox News, contributor Morgan Ortegus found the idea of Manafort banking on a Trump pardon "a little fanciful ... especially considering that there are still state crimes to be tried for which the president wouldn't have pardon authority." She said former FBI officials she spoke with think Mueller's court filing was "quite suspicious, that maybe there wasn't the case of Russian collusion that perhaps they would get out of Mueller once he started to testify."

You can watch more former federal prosecutors analyze the Corsi case at CNN. Peter Weber