Kill the mandatory data retention policy, Greens leader Scott Ludlam has urged.
In a statement on his website, the senator slammed the Australian government's plan to force ISPs to store data about their customers two years.
"It is time to kill the mandatory data retention policy once and for all," Ludlam said.
The government has offered contradictory explanations of what will be stored under such a scheme.
Attorney-General George Brandis defended the data retention program in a Sky News interview on Wednesday night, but the conversation only served to raise more questions from critics about the scope of the program.
Many concluded from the interview that details of which websites were accessed by ISP customers would be retained.
Communications Minister Malcolm Turnbull sought to clarify the scope of the scheme in an ABC Radio interview this morning, saying that proposed data retention laws would require ISPs to retain records of the IP address used by customers of their service and not the IP addresses of websites visited by customers.
"This week's blundering attempt by [Prime Minister] Tony Abbott and his embarrassing Attorney General George Brandis to enforce a mandatory data retention policy including all website visits has crossed a line, and will be fiercely challenged," Ludlam said.
The potential of the Internet to be used for both free speech and its suppression, including the impact of data retention, was discussed on Thursday at a free speech symposium organised by the Human Rights Commission.
Swinburne Institute for Social Research professor Julian Thomas spoke at the event about the potential for the Internet to be used for both free speech and suppression.
“The Internet makes an incredible contribution to freedom of expression and vibrant political debate in this country,” said Thomas.
“That idea of the Internet as a kind of potential liberal machine continues to very powerfully shape our expectations of what it can do. But that image of a technology of freedom has been complicated dramatically by recent and very hard experience and real uncertainty.”
The Swinburne professor pointed to the existence of “dystopian and utopian” views of the Internet.
“We’ve discovered that the technologies of freedom can also be technologies of ‘unfreedom’,” he said.
“We know that the Internet can also work as a system for control and suppression. And that level of surveillance has taken most of us as naïve users of the Internet, anyway, by surprise.”
At the same event, Human Rights Commissioner Tim Wilson warned that implementing mandatory data retention laws could discourage free speech in Australia.
"One wonders when you have a situation where mass surveillance through data retention may amount to having a chilling effect on free speech as well in the information we choose to seek and impart," Wilson said.