MPs are being warned that tweets they send from the debating chamber aren't covered by parliamentary privilege.
"Members should be aware that anything said on social media is potentially actionable in court," the privileges committee says in a just-released report.
Parliamentary privilege protects MPs from legal action when they speak in Parliament.
However, the committee supports the use of social media by MPs and says it's a "positive development".
"A healthy democracy relies on public participation, and all communication channels need to be fully used to promote the work that occurs in the House of Representatives."
Speaker David Carter asked the committee, which deals with behaviour in Parliament, to consider the increasing use of social media by MPs and the tweets they send out during debates.
"We have no intention of questioning whether members and others should use it to report on parliamentary proceedings," the report says.
The committee isn't happy about MPs using their cellphones to take photos in the debating chamber or in select committees.
"Regrettably, on a small number of occasions, a member has taken a photo of another member without permission and used it for political advantage," it says.
"We consider this is unacceptable."
It recommends Mr Carter issue guidelines.