1868 impeachment managers investigation

On May 16, 1868, the United States House of Representatives authorized the impeachment managers (prosecutors) of the impeachment trial of Andrew Johnson to conduct an investigation into possible "improper or corrupt means" to influence the vote of members of the United States Senate in the impeachment trial. The investigation was launched before the adjournment of the trial and continued after the trial adjourned on May 26, 1868. The leading figure of the investigation was Benjamin Butler. The final report of the investigation was published on July 3, 1868.