Several Democrats have claimed that the Trump administration's Jan. 3 military operation that led to the capture of Venezuelan President Nicolás Maduro and his wife, Cilia Flores, was "illegal," violating both domestic and international law. Experts we consulted told us that the operation runs afoul of the United Nations Charter that prohibits unjustified uses of military force by one country against another. Experts also previously told us that the U.S. Constitution, according to an originalist interpretation, requires congressional approval for such use of force abroad. In practice, however, multiple presidents — like President Donald Trump in this instance — have unilaterally ordered military action without input from lawmakers. In this story, we'll review some of the legal arguments that have been made.