MSNBC’s Joy Reid on Sunday wondered if President Donald Trump might barricade himself inside the White House if he were subpoenaed to testify before Special Counsel Robert Mueller’s grand jury.

“Normally, a person who refuses to testify before a grand jury winds up being incarcerated for the time period of the grand jury, which can be up to 18 months,” former Watergate lawyer Nicholas Akerman told Reid. “So, one way to enforce it is to have Donald Trump taken by the federal marshals and put in federal prison until he testifies.”

Reid then wondered what would happen if the president simply refused to let federal marshals into the White House to arrest him. “What if he refuses to, uh, open the White House door? What if he fires any Secret Service agent who would allow the federal marshals in?” Reid asked. “What if Donald Trump decides, ‘I don’t’ have to follow the law. I refuse to be held under the law. No marshal can get into the White House and any secret service agent that defies is fired’?”

“Well, at some point, he’s gonna have to come out of the White House,” Akerman replied, “At some point he’s gonna have to leave.”

Eventually, when he did leave the White House, Akerman said, “The U.S. Marshals will be directed to take him into custody, bring him before the federal district court judge. He’ll be basically told that either he goes in and he testifies or he takes the Fifth Amendment. If he takes the Fifth Amendment, there’s not a problem. If he refuses to answer on the ground that a truthful answer would tend to incriminate him, he has the right to do that. If he does that, there’s no contempt. If he doesn’t do that, he can be directed to go directly to jail, do not pass go, do not collect $200. End of story.”

President Trump has not been subpoenaed to testify.

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