The Federal Government has announced it will proceed with controversial plans to censor the internet after Government-commissioned trials found filtering a blacklist of banned sites was accurate and would not slow down the internet.

But critics, including the online users' lobby group Electronic Frontiers Australia and the Greens communications spokesman Scott Ludlam, said the trial results were not surprising and the policy was still fundamentally flawed.

The Communications Minister, Stephen Conroy, said today he would introduce legislation just before next year's elections to force ISPs to block a blacklist of "refused classification" (RC) websites for all Australian internet users.

-------------------------------------------------------------
POLL: What do you think of the proposed filter?
-------------------------------------------------------------

The blacklist, featuring material such as child sex abuse, sexual violence and instructions on crime, would be compiled using a public complaints mechanism, Government censors and URLs provided by international agencies.

Senator Conroy also released results from a pilot trial of ISP-level internet filters, conducted by Enex Testlab, which he said found that blocking banned material "can be done with 100 per cent accuracy and negligible impact on internet speed".

"Most Australians acknowledge that there is some internet material which is not acceptable in any civilised society," he said.

"It is important that all Australians, particularly young children, are protected from this material."

He said about 15 western countries had encouraged or enforced internet filtering, and there was no reason why Australians should not have similar protection.

It is not clear how - or if - the filters will distinguish between illegal RC material and that which is perfectly legal to view.

An earlier version of the Government's top-secret list of banned sites was leaked on to the web in March, revealing the scope of the filtering could extend significantly beyond child porn.

About half of the sites on the list were not related to child porn and included a slew of online poker sites, YouTube links, regular gay and straight porn sites, Wikipedia entries, euthanasia sites, websites of fringe religions such as satanic sites, fetish sites, Christian sites, the website of a tour operator and even a Queensland dentist.

"Given the pilot's modest goals, it was designed from the beginning to pass," said EFA spokesman Colin Jacobs.

"Although it may address some technical issues, what it leaves out is far more important - exactly what will be blocked, who will decide, and why is it being attempted in the first place?"

Similarly, Senator Ludlam said: "Nobody said that filtering from a static list of URLs was going to slow things down too much unless the list gets huge, so I don't think they've already proven anything that we don't already know."

The pilot trial report also noted that motivated people could circumvent any internet filters with ease, which Senator Ludlam and Jacobs said called the effectiveness of the proposal into question.

Ludlam said proving a technical case was not the same as proving the wisdom of going down the internet censorship track in the first place, which he said had always been two separate discussions.

"While the Government says that they will be relying on an evidence-based policy, we still haven't seen evidence that this is going to play any meaningful role in preventing children from accessing harmful material online," Senator Ludlam said.

Jacobs said: "Successful technology isn't necessarily successful policy. We're still yet to hear a sensible explanation of what this policy is for, who it will help and why it is worth spending so much taxpayer money on."

Peter Coroneos, chief executive of the Internet Industry Association, said he would be meeting with his members tonight to discuss the report before formulating a response.

Senator Conroy said the Government would immediately undertake public consultations, starting today with the release of a discussion paper on additional measures to improve the accountability and transparency of processes that lead to sites being placed on the blacklist.

Some of the options raised include appeal mechanisms, notification to website owners of RC content and the review by an independent expert.