“He saw everything,” said a Republican consultant who worked with Gates during the campaign. The consultant called Gates one of the “top five” insiders whom Mueller could have tapped as a cooperative government witness. One defense attorney in the case said that Gates’s plea has triggered palpable alarm in Trump world…

[V]eteran law enforcement experts said that Mueller would only grant Gates leniency on his prison sentence in return for his unrestricted testimony about subjects ranging well beyond his work with Manafort.

“He’s their bitch,” said Solomon Wisenberg, a former Starr deputy.

Gates is already enjoying some benefits from his cooperation. He is free on $5 million bail and living at his home in Richmond, and was recently granted permission to take a spring break trip with his family to Boston—though he rearranged the trip over security concerns. (In a court filing, his lawyer cited an online comment that warned: “Bring a food taster.”)