Simon Heffer in the Daily Mail write an article about it before Tapsell made his speech
"In Britain, impeachment is the process by which the House of Commons votes to have someone, usually but not inevitably a high public official, put on trial before the House of Lords for alleged crimes, or for criminally damaging the public interest.
A Select Committee of MPs draws up the evidence to take this serious step, and would provide prosecutors to pursue the case before the Lords.
A simple majority is required to convict, at which point a sentence can be passed, which could, in theory, involve Tony Blair being sent to prison.
The defendant can have his own legal representation, and the case can be presented in every bit as much detail as in a court of law.
No one has been impeached since 1806 — the last was a peer named Lord Melville, accused of misappropriating public funds from the Admiralty during the Napoleonic Wars. He was acquitted, but he never held office again.
In 1999, a Select Committee decreed the procedure was obsolete, and in a modern parliamentary democracy was unnecessary. But perhaps the allegations levelled at Mr Blair have proved them wrong."
www.dailymail.co.uk/debate/article-2659649/Impeach-Tony-Blair-As-Iraq-burns-Parliament-deluded-liar-trial-writes-SIMON-HEFFER.html#ixzz359yFH7zt