The involvement of Mrs. Lincoln may help explain the vigor of the committee’s pursuit. John Hickman, the severe-looking chairman, was an eloquently anti-slavery Republican from Pennsylvania who presumably shared many northerners’ scorn for the president’s wife. Besides having a brother, three half-brothers, and three brothers-in-law in the Confederate army, Mrs. Lincoln was assailed for lavishly redecorating the Executive Mansion while Union soldiers needed blankets. Earlier in February, the press had pilloried the First Lady (to whom that term was first applied, by the correspondent for The Times of London) for putting on an “ostentatious” and “most unseemly” White House ball.

Chairman Hickman also had reason to attack the New York Herald, which had knocked him in 1860 as “only a fighter with his tongue.” The committee subpoenaed Wikoff, who confessed his own role in informing the Herald of the main points of the president’s address. But he refused to reveal how he had learned of them. For this, he was held in contempt of Congress and jailed.

Wikoff was confined in a rat- and roach-infested storeroom in the Capitol’s subbasement, attended by a Newfoundland named Jack. For a dandy who showed (a biographer wrote) a “slightly hysterical reaction to any situation,” one night was enough.

He had help in getting out. Daniel Sickles, another of the capital’s peacocks, went to the White House on his behalf. As a congressman, Sickles had shot and killed his wife’s lover on a Washington street (and won acquittal on the unprecedented grounds of temporary insanity). Now a brigadier general known for his political skills, he visited Wikoff’s unfortunate quarters the next morning, passing himself off as the prisoner’s counsel.

Their conversation prompted Wikoff to send a note to Chairman Hickman that he was ready to talk. The sergeant-at-arms brought the witness back before the committee, where he dumbfounded the members when he named his source for the leak: none other than the White House gardener, John Watt. Watt confessed the following day, telling the committee the unlikely story that he had seen the message in the president’s library, memorized passages, and recited them to Wikoff.

But why would the gardener admit guilt for something he hadn’t done? Well, he was in a legal tangle of his own. The month before, another House committee had accused him of secessionist sympathies. Worse, he was engaged in blackmail. As an expert at padding invoices, he had taught the skill to Mrs. Lincoln, whose social and decorative ambitions exceeded Congress’s purse. Now he was demanding $20,000 in exchange for three of Mrs. Lincoln’s incriminating letters. Accepting blame for leaking the president’s message, Watt lost his White House job but landed a $1,500 per year sinecure at the Patent Office.