There is often confusion about what impeachment means and whether President Clinton is already impeached or must wait for the outcome of his Senate trial.
Mr Clinton was impeached on December 19th, when the House of Representatives voted that he was "impeached for high crimes and misdemeanours". Two articles of impeachment were approved and two rejected. The approved articles charge him with perjury and obstruction of justice.
The US Senate has now begun the "impeachment trial" of President Clinton - that is, the trial based on his impeachment on the charges in the articles. If a two-thirds majority of the 100 senators convicts him of the charges in one or both of the articles, the President will be removed from office.
So President Clinton has already been impeached by the House. It is for the Senate to convict him or not on the impeachment charges.
