During the trial, the prosecution offered by the impeachment managers that the House had appointed argued that Johnson had explicitly violated the Tenure of Office Act by dismissing Stanton without the consent of the Senate.

One of the points made by the defense was that ambiguity existed in the Tenure of Office Act that left open a vagueness as to whether it was actually applicable to Johnson's firing of Stanton.

They further argued that Johnson was acting in interest of the necessity of keeping the Department of War functional by appointing Lorenzo Thomas as an interim officer, and that he had caused no public harm in doing so.

The tenth article charged Johnson with attempting, "to bring into disgrace, ridicule, hatred, contempt, and reproach the Congress of the United States", but did not cite a clear violation of the law.

[19] The House Republican caucus had met March 1, 1868 (the previous night) to hold an internal vote to determine a consensus on whom they would support to be impeachment managers.

[19] After the tellers were named, Luke P. Poland nominated Bingham, Boutwell, Butler, Logan, Stevens, Williams, and Wilson to serve as impeachment managers.

[54] Many members of the House of Representatives crowded on the floors and the lobbies of the Senate chamber, including James Mitchell Ashley (who had been among the earliest and fiercest proponents of impeaching Johnson) and Speaker Colfax.

[38] A key argument made by the prosecution was an assertion that Johnson had explicitly violated the Tenure of Office Act by dismissing Stanton without the Senate's consent.

To support the legality of the Tenure of Office Act, Butler cited historical precedents, including past laws of Congress and writings by Alexander Hamilton in The Federalist Papers.

[24] One of the key points argued by the defense was that the language in the Tenure of Office Act was not clear, leaving vagueness as to whether the legislation itself was even applicable to the situation involving Stanton.

[24] Another argument made by the defense was that Johnson was only acting, by necessity, to keep a staffed and operational Department of War by appointing Lorenzo Thomas an interim officer.

[74] Defense counsel Benjamin Robbins Curtis called attention to the fact that after the House passed the Tenure of Office Act, the Senate had amended it, meaning that it had to return it to a Senate-House conference committee to resolve the differences.

He followed up by quoting the minutes of those meetings, which revealed that while the House members made no notes about the fact that their sole purpose was to keep Stanton in office, and that the Senate had disagreed with that being the intent.

[38] As a witness for the defense, Gideon Welles testified that Johnson's Cabinet had advised the president that the Tenure of Office Act was unconstitutional, and both Secretaries William Seward and Edwin Stanton had agreed to create a draft of a veto message.

These were William P. Fessenden (R– ME), Joseph S. Fowler (R– TN), James W. Grimes (R– IA), John B. Henderson (R– MO), Edmund G. Ross (R– KS), Lyman Trumbull (R– IL), Peter G. Van Winkle (R– WV).

In his statement explaining his votes for acquittal, Republican Lyman Trumbull argued that, while Johnson was unfit for the presidency, it would be wrong to remove him for misconstruing a law that there was reason for doubt about.

Blinded by partisan zeal, with such an example before them, they will not scruple to remove out of the way any obstacle to the accomplishment of their purposes, and what then becomes of the checks and balances of the Constitution, so carefully devised and so vital to its perpetuity?

"[90] Some possible factors that the acquitting Republican Senators may have taken into account was that Johnson was already in the final year of his presidency, and it appeared certain that he would not be nominated by either major party in the 1868 presidential election.

[94][95][96] News of the vote was greeted with joy by many individuals aligned with Johnson across the nation, with there being public celebrations in several cities, particularly among crowds that had congregated near the bulletin boards of newspaper offices to await word on the verdict.

[38] During the hiatus the House voted 79–26 on May 16 to approve a resolution introduced by John Bingham that enabled the impeachment managers to investigate alleged "improper or corrupt means used to influence the determination of the Senate" and to appoint subcommittees to take testimony.

A handful of senators wanted the trial to adjourn until the end of June to allow the impeachment managers to collect more evidence in their investigation into potential corruption before a vote was held.

[81] After the vote to adjourn the trial, Edwin Stanton effectively ended his fight against his dismissal, and instructed his assistant adjunct general to take leadership of the War Department, "subject to the disposal and directions of the president."

[38] The platform adopted at the 1868 Republican National Convention in May 1868 declared that Johnson had been, "justly impeached for high crimes and misdemeanors, and properly pronounced guilty thereof by the vote of thirty-five senators".

[25] Some have argued that the acquittal was an acknowledgement of an understanding that impeachment should be used to address abuses of power and violations of public trust, but not as a means for settling political and policy disputes between the Congress and a president.

[111] In the aftermath of the trial, Ream was initially ordered to vacate Room A of the United States Capitol, which she had been using as a studio for sculpting her government-commissioned statue of Abraham Lincoln.

[111][112][113] However, Ream received support from powerful New York sculptors and the assistance her friend Thaddeus Stevens (who had been an impeachment manager) in securing the subsequent passage of a resolution by the House granting her permission to utilize the space as a studio for another year.

[14][38][116] On March 26, shortly after the Senate trial adjourned, the impeachment managers returned to question Charles Woolley, the Johnson allied lawyer that had been forcefully brought before it by the House's sergeant at arms.

James W. Grimes received assurances that acquittal would not be followed by presidential reprisals; Johnson agreed to enforce the Reconstruction Acts, and to appoint General John Schofield to succeed Stanton.

He hoped the timing of the report's release, a week before the 1868 Democratic National Convention was to be held in New York City, might harm Johnson's chance of receiving his party's nomination.

[119] While the Tenure of Office Act was repealed by Congress in 1887, subsequent opinion by the Supreme Court of the United States appear to support the position that Johnson was constitutionally entitled to fire Stanton without congressional approval.