He had not tried to overturn Grant’s election. He had not obstructed the peaceful transfer of power. (But like Mr. Trump, he refused to attend his successor’s inauguration.) He had committed an abuse of power by usurping the office of Congress, which has the right to determine the qualifications of its own members — all the more critical after a civil war in which 11 states were in revolt.
As for inciting or aiding an uprising, that was debatable. Though a staunch Unionist, Johnson had watched silently in 1866 during the New Orleans Massacre that prevented a state convention from amending its constitution to give black men the right to vote. The crowd consisted of members of the New Orleans Police Department, which was largely made up of former rebels. They were supported by the mayor, a Confederate sympathizer, imprisoned as a traitor during the war and elected even before he was pardoned.
An 1867 congressional inquiry into that tragedy reported that more than 35 people, the vast majority of whom were black, had died and about 145 people were injured. It also established that the massacre would never have happened without Johnson’s tacit approval. The abolitionist Wendell Phillips predicted that “what New Orleans is today, Washington will be” – “ruled by the president and his mafia.”
In 1868, when he was finally impeached, the 10th article of impeachment accused Johnson of ridiculing Congress and overriding his authority, and the 11th article concerned obstruction of his laws. When Ohio Representative John Bingham argued for the president’s conviction during the impeachment trial, he reminded senators that “no one is above the law; that no one lives for himself alone, “but each for all.” With tears in his eyes, he concluded that ‘position, however high, patronage, however powerful, cannot be allowed to shield crime from danger to the Republic’.
But since the Senate did not convict Andrew Johnson, there was no way to disqualify him from office. He may have abused power, ridiculed Congress, usurped for himself a form of Reconstruction that entrenched white supremacy, but the moot criminal charge (in violation of the Tenure of Office Act) did not hold up — and even if it did, it was it was an impeachment tribunal, not a court, that had charged him.