MSNBC legal analyst explains how Mueller will eventually bag Trump

A former top law enforcement official explained that President Donald Trump could stall the special counsel probe from the White House -- but he couldn't outrun Robert Mueller forever.

Chuck Rosenberg, a former U.S. Attorney and head of the Drug Enforcement Agency, told MSNBC that Mueller would eventually get his way if he wanted to force Trump to testify.

"Normally, the person who is being questioned -- target, subject, defendant -- does not determine what is and what is not a legitimate line of questioning," Rosenberg said. "That's just crazy."

"So if this thing has to be litigated -- for instance, if Bob Mueller decides he needs the president's testimony on the obstruction issue and wants to push that issue," he added, "it'll be decided by a court, not by White House counsel, not by Mr. Trump's personal lawyers. It'll be decided by a court. By the way, for what it's worth, I think the court precedents line up nicely for the prosecutors in this."

Rosenberg and others have speculated that a sealed case involving Mueller might be litigation to resolve a possible presidential subpoena -- but he said Trump could face legal jeopardy even if he's protected by the office he currently holds.

"If the president is a target of this investigation, what we call someone likely to be charged, policy is you don't issue a grand jury subpoena in the normal course to a target," he said.

"Then, putting that aside for a minute, you also know that you can't charge a sitting president," Rosenberg added. "If you can't charge a sitting president, could he be a target? I think the answer is yes, even though it sounds contradictory. Because one day, he won't be a president anymore. He could be a target today and a defendant later."