In the case of Belknap v. United States in 1893, the U.S Supreme Court ruled that a person could not be prosecuted for an act committed while they were a government official after they had left office. The case involved William W. Belknap, who was Secretary of War under President Grant and was impeached by the House of Representatives for allegedly accepting bribes. However, he resigned before his trial in the Senate began. The Senate decided to proceed with his trial despite his resignation but acquitted him because many senators believed that they lacked jurisdiction over former officials. This led to legal proceedings against him in civil court where he argued that since he had already been tried by impeachment (a political process), trying him again would constitute double jeopardy (being tried twice for the same crime). The Supreme Court agreed with this argument and dismissed charges against Belknap.

In the dissenting opinion for Belknap v. United States, the justices argued that William W. Belknap, as a former Secretary of War who had resigned from his position, could not be impeached by the Senate because he was no longer a civil officer of the U.S., which is required under Article II Section 4 of Constitution to proceed with impeachment. They believed that once an official has left their office voluntarily or involuntarily, they are beyond reach of impeachment process and any subsequent trial in Senate would have no jurisdiction over them. This view held that impeachment should serve only as removal mechanism rather than punishment for past actions while in office; therefore if someone is already out of office at time proceedings begin there's nothing to remove them from thus rendering whole exercise moot and unconstitutional.