The Speaker is warning MPs who get carried away on Twitter they could find themselves pursued in the courts.
David Carter says there are no clear rules for MPs tweeting in the debating chamber and has referred the matter to the Privileges Committee to investigate.
United Future leader Peter Dunne does not want the use of the micro-blogging service restricted, but wants the rules made clear.
Mana Party leader Hone Harawira said tweets by MPs from the House should be protected by parliamentary privilege.
But Green MP Kevin Hague said MPs should be accountable for what they tweet, regardless of whether they are in Parliament or not.