Whatever he (or anyone) says in Parliament or one of its
committees or in a court of law is absolutely privileged. He cannot
be sued even if he used vulgarities against the PM and his mother.
However, he can be ejected from Parliament by the Speaker through
the parliamentary rules but no legal proceedings against him.
If you want to defame anyone, you put it in an affidavit (which
might be leaked to the press through no fault of yours 
) or say it in court. Lawyers do it all the
time....the judge can stop you but you cannot be sued..
