Full context:   Congress's oversight function takes many forms: The executive branch is established in Article Two of the United States Constitution, which vests executive power in the president of the United States. The president is both the head of state (performing ceremonial functions) and the head of government (the chief executive). The Constitution directs the president to "take care that the laws be faithfully executed" and requires the president to swear or affirm to "preserve, protect and defend the Constitution of the United States." Legal scholars William P. Marshall and Saikrishna Prakash write of the Clause: "the President may neither breach federal law nor order their subordinates to do so, for defiance cannot be considered faithful execution. The Constitution also incorporates the English bars on dispensing or suspending the law, with some supposing that the Clause itself prohibits both." Many presidential actions are undertaken via executive orders, presidential proclamations, and presidential memoranda.