But according to the U.S. Constitution, the President has no such authority to overturn his predecessor’s pardons, especially not based on the type of signature, legal experts say. “The Constitution doesn’t even require that the pardon be written, so the idea that the signature is by autopen rather than by handwritten signature seems not relevant to the constitutionality because Article II just says that the President has the power to pardon,” says Bernadette Meyler, a Stanford Law School professor and constitutional law expert.