Ulysses S. Grant was reportedly arrested while in office in 1872 for speeding in his horse-drawn carriage on the streets of Washington, D.C. The arrest was made by a police officer named William H. West of the Metropolitan Police Department, who caught Grant speeding despite a prior warning. Grant apologized but was caught speeding again the next day, leading to his arrest. He was taken to the police station where he paid a $20 bond but did not appear in court, forfeiting the bond. This incident, if it indeed happened, makes Grant the only U.S. president to have been arrested while in office. The story was kept quiet for decades and confirmed much later, though some historians question its historicity due to a lack of contemporaneous records. Grant reportedly respected the officer's duty, setting a symbol of the rule of law despite his presidential status.
