Close but no cigar? Boris Johnson MP would like to impeach the PM

Over a dozen MPs have called for a Commons debate to examine Tony Blair's record on Iraq.

Plaid Cymru is optimistic about securing the debate, but Labour's majority and the whips' discipline should preclude the completion of the process.

The arcane procedure would certainly bring drama to the Legislature: pomp and ceremony, the public arrest of the prime minister and court proceedings in the auspicious surroundings of Westminster Hall with Tony Blair in the dock.

BBC Parliament examines the long dormant power of impeachment.

The Speaker's Office has made no comment on what might be said if this point of order is moved but if the debate is permitted, the prime minister's alleged high crimes will be debated, and then voted on.

In the unlikely event of the government being defeated in the division the Commons will witness the most dramatic event in the Palace of Westminster in modern times: the prime minister will be arrested.

Adam Price will then be ordered to the House of Lords where he will inform peers that impeachment proceedings have started.

He will tell the Upper House that the articles for his impeachment will be presented to them "in due time."

When the articles are formally presented to the Lords, peers will set a date for the trial.

The Lords would act as jury, and the Commons would put forward 'managers' to act as the counsel for the prosecution.

The prime minister would be able to put his case and call witnesses.

When all sides have presented their evidence, the Lord Chancellor, who presides over the trial, would ask the peers whether the prime minister is guilty or not guilty on each article of impeachment.

The bible of Parliamentary practice, Erskine May, describes the procedures: "The peers in succession rise in their places when the question is put, and standing uncovered, and laying their right hands upon their breasts, answers, 'guilty', or 'not guilty', as the case may be."

If the prime minister is found not guilty, impeachment is dismissed.

But if a guilty verdict is returned the drama continues.

Judgement is formally declared in a sitting of the House of Lords.

Black Rod would march to the Commons and invite the 'managers' to hear the judgement.

The prime minister would also be called to the bar of the Lords to hear the Lord Chancellor pronounce the decision.

MPs have the final say on sentencing.

Calling a general election will not prevent the wheels of impeachment turning. The allegations survive both the end of the Parliamentary year and even dissolution.

Keep your eyes on BBC Parliament after the summer recess to see how far this exciting process goes