According to The History Place, President Bill Clinton was impeached for committing two acts of perjury, one act of obstruction of justice and one act of abuse of power to commit perjury. The investigations involved Clinton's extramarital affair with Monica Lewinsky and Paula Jones' allegations of sexual harassment.
Two of the acts of perjury involved lying about the extra-marital affair with Monica Lewinsky. The other count and the obstruction of justice charge involved the sexual harassment case regarding Paula C. Jones. The prosecuting attorney was Kenneth Starr. Other allegations of sexual misconduct by the former president were reported but have not been proven.