The search on former U.S. President Donald Trump’s home in Florida was unprecedented, but there is no guarantee that the Justice Department ultimately will bring a criminal case that would be fraught with political landmines and untested legal questions.

Federal investigators on Monday descended on Mar-a-Lago as part of an investigation into whether Trump took classified documents from the White House when he left office, an explosive development that risks hanging over his possible run for the presidency in 2024.

"I am not aware of any prior case where a search warrant was executed at the home of a former president,” said Barbara McQuade, a law professor at the University of Michigan and a former federal prosecutor. "Even President Nixon received a subpoena for his recordings.”