Before we come to Prime Minister's questions, I wish to make a statement about the House

practices regarding accusing members of lying or deliberately misleading the House.

I recognise there are frustrations around the House's practices.

Firstly, let me say that there are means by which accusations of lying may be brought before

the House, including by means of a substantive motion.

The Scottish National Party did so on their opposition day in November.

However,

Members may not accuse each other of lying or deliberately misleading the House unless such a substantive motion is under consideration.

Erskine May is clear that it is to preserve the character of parliamentary debate,

which I take to mean to stop it

descending into fruitless titles of accusation and counter-accusation.

May I also say that expressions when used in respect of the members, which are regarded

with particular seriousness, generally leading to prompt intervention from

the Chair, and often a requirement on a Member to withdraw the words, include charges uttering

deliberate falsehoods. It is important to stress context. Similar words said in different proceedings

might attract a different response

from the Chair, depending on the subject being debated, tone and other considerations,

but in general the Chair will not tolerate accusations of lying or deliberately misleading

the House. That is the long-standing practice of the House, as set

out in asking May and followed by successive speakers and deputy speakers. Of course, long-standing

practices may change, for example, if the House decided it wanted a different approach,

perhaps informed by the Procedure Committee inquiry, but it's not for me to change the practice

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