The Speaker's role in the Commons is to act as Chairman
during debates, and to see that the rules of business are
observed. An important function is to select members to
speak - a task which must be carried out with great tact
and knowledge of the subject matter. The Speaker also
maintains discipline - directing members to withdraw
inappropriate remarks, and even suspending sittings if
proceedings get out of hand. The Speaker and her three
deputies do not vote in Divisions. She does, however, have
a casting vote if there is a tie - so do the deputies if they happen to
be in the chair at the time.
The Speaker is the Commons' spokesperson on ceremonial and formal occasions. Nowadays this is usually a happy task, but in the past Speakers were often required to deliver unwelcome messages to the monarch.