Why might Andrew Johnson’s conviction and removal have weakened the office of president?

At the end of a historic two-month trial, the U.S. Senate narrowly fails to convict President Andrew Johnson of the impeachment charges levied against him by the House of Representatives three months earlier. The senators voted 35 guilty and 19 not guilty on the second article of impeachment, a charge related to his violation of the Tenure of Office Act in the previous year. Ten days earlier, the Senate had likewise failed to convict Johnson on another article of impeachment, the 11th, voting an identical 35 for conviction and 19 for acquittal. Because both votes fell short–by one vote–of the two-thirds majority needed to convict Johnson, he was judged not guilty and remained in office.

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