The Australian Federal Police has confirmed it has collected phone and internet data on up to four federal MPs.
Australia's relationship with Indonesia is in crisis after it was revealed Australian spies tried to tap president Susilo Bambang Yudhoyono's phone.
But on Monday night, while reporters were diverted by news about the allegations regarding Indonesia, the AFP was being grilled in Senate Estimates.
In a lengthy exchange on the collection of metadata, Senator Nick Xenophon asked AFP Chief Commissioner Tony Negus how many members of parliament had been the subject of authorisation orders allowing the AFP to track their phone calls and email traffic.
Metadata is the information contained in phone and internet traffic, including who is called or emailed, when and for how long, but not what was said.
An authorisation order refers to a request for approval to search the metadata records.
Recording what was said is known as an "interception" and the AFP was less forthcoming on whether any politicians have had their communications intercepted.
But even if they had, the Chief Commissioner told the Senate the AFP may not even be able to confirm that it had been done, because of proscriptions under the telecommunication interception act about releasing elements of that sort of data.
The AFP would not confirm which politicians had been under investigation, but Senator Xenophon says the implications of metadata surveillance are significant.
"The effect that can have on a democracy, on people coming forward with important information in the public interest, can be quite chilling," he said.
He hosted a special briefing at Parliament House yesterday for journalists, politicians and staffers.
Some senators, including Greens Senator Scott Ludlum, said they will be pushing for legislative changes to protect their information.
"Firstly we need to sweep out that not every agency and its collective dog can get metadata by filling out a piece of paper," he said.
"The real test for this Parliament is at what point do you need to get a warrant for a metadata.
"Because if you can track an individual's movement around the landscape at every time of day or night and mine their entire social network, that should require a warrant for the same reason that tapping your phone should require one."
Although a metadata search does not disclose what was said or written in the communication, it does track who was called and where the calls were made form.
Senator Xenophon said this was the crucial bit of information that would deter whistleblowers from coming forward to politicians or journalists.
Senator Xenophon said Australia needed to be more in line with the sort or privacy protections in place in the United States.