On January 7, 1999, the impeachment trial of President Bill Clinton, formally charged with lying under oath and obstructing justice, begins in the Senate. As instructed in Article 1 of the U.S. Constitution, Supreme Court Chief Justice William Rehnquist was sworn in to preside, and the senators were sworn in as jurors. Congress had only attempted to remove a president on one other occasion: the 1868 impeachment trial of President Andrew Johnson, who incurred the Republican Party’s wrath after he proposed a conservative Reconstruction plan.

In November 1995, Clinton began an affair with Monica Lewinsky, a 21-year-old unpaid intern. Over a year and a half, the president and Lewinsky had nearly a dozen sexual encounters in the White House. In April 1996, Lewinsky was transferred to the Pentagon. That summer, she first confided in Pentagon co-worker Linda Tripp about her sexual relationship with the president. In 1997, with the relationship over, Tripp began secretly to record conversations with Lewinsky in which she gave details about the affair.

In December, Lewinsky was subpoenaed by lawyers for Paula Jones, who was suing the president on sexual harassment charges. In January 1998, allegedly under the recommendation of the president, Lewinsky filed an affidavit in which she denied ever having had a sexual relationship with him. Five days later, Tripp contacted the office of Whitewater Independent Counsel Ken Starr to talk about Lewinsky and the tapes she made of their conversations. Tripp, wired by FBI agents working with Starr, met with Lewinsky again, and on January 16, Lewinsky was taken by FBI agents and U.S. attorneys to a hotel room where she was questioned and offered immunity if she cooperated with the prosecution. A few days later, the story broke, and Clinton publicly denied the allegations, saying, “I did not have sexual relations with that woman, Ms. Lewinsky.”

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In late July, lawyers for Lewinsky and Starr worked out a full-immunity agreement covering both Lewinsky and her parents, all of whom Starr had threatened with prosecution. On August 6, Lewinsky appeared before the grand jury to begin her testimony, and on August 17, President Clinton testified. Contrary to his testimony in the Paula Jones sexual-harassment case, President Clinton acknowledged to prosecutors from the office of the independent counsel that he had had an extramarital affair with Ms. Lewinsky.

In four hours of closed-door testimony, conducted in the Map Room of the White House, Clinton spoke live via closed-circuit television to a grand jury in a nearby federal courthouse. He was the first sitting president ever to testify before a grand jury investigating his conduct. That evening, President Clinton also gave a four-minute televised address to the nation in which he admitted he had an inappropriate relationship with Lewinsky. In the brief speech, which was wrought with legalisms, the word “sex” was never spoken, and the word “regret” was used only in reference to his admission that he misled the public and his family.

Less than a month later, on September 9, Kenneth Starr submitted his report and 18 boxes of supporting documents to the House of Representatives. Released to the public two days later, the Starr Report outlined a case for impeaching Clinton on 11 grounds, including perjury, obstruction of justice, witness-tampering, and abuse of power, and also provided explicit details of the sexual relationship between the president and Ms. Lewinsky.

On October 8, the House authorized a wide-ranging impeachment inquiry, and on December 11, the House Judiciary Committee approved three articles of impeachment. On December 19, after nearly 14 hours of debate, the House approved two articles of impeachment, charging President Clinton with lying under oath to a federal grand jury and obstructing justice.

Clinton, the second president in American history to be impeached, vowed to finish his term. On January 7, 1999, the impeachment trial began. Five weeks later, on February 12, the Senate voted on whether to remove Clinton from office. Clinton was acquitted on both articles of impeachment. The prosecution needed a two-thirds majority to convict but failed to achieve even a bare majority. Rejecting the first charge of perjury, 45 Democrats and 10 Republicans voted “not guilty,” and on the charge of obstruction of justice the Senate was split 50-50. After the trial concluded, President Clinton said he was “profoundly sorry” for the burden he imposed on Congress and the American people.

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