Paul Manafort may have been duping Rudy Giuliani for the last few weeks: MSNBC's Ari Melber

Today's guilty plea and cooperation deal with former Donald Trump campaign chairman Paul Manafort are causing legal watchers to wonder how the commander-in-chief's legal team were caught so flat-footed by the plea deal.

"'They did not see it coming.' That's a quote from how one expert on the how the Mueller probe is describing Donald Trump's legal team's reaction at this hour," MSNBC's Ari Melber reported. "Trump's lawyer looks surprised, because over the past few days they were publicly boasting that Manafort was still on their team, Rudy Giuliani touting coordination with Manafort's lawyers and even telling reporters they had an active joint defense agreement."

“A new question is whether the facts just changed quickly, or whether Manafort’s side was actively duping his former boss at the White House,” Melber explained.

"And that brings us back to the blind siding point," Melber noted.

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