The new voluntary Web content filtering system for ISPs is expected to be up and running within a matter of weeks.

Meanwhile, the Department of Internal Affairs has moved to counter claims by the local blogging community that the  system is a form of censorship by stealth.

Bloggers have expressed concern about a perceived lack of transparency in the process; that while ISPs have the  option to use filtering, their customers don’t; and that once you start filtering sites containing one sort of content (in this  case child sexual abuse), what comes next?

“Our intention really is simply providing a service to the public,” Steve O’Brien, head of the DIA’s Censorship  Compliance Unit, told NetGuide. “These are not grey areas – this is very horrific material which is illegal to possess. If  you were to distribute that material you could face up to a 10-year prison sentence.

“We’re not talking censorship – we’re talking material that is illegal in New Zealand and we’re focusing purely on child  sexual abuse images. Each of those pictures is a crime scene in itself. We’re not trying to say this is a silver bullet –  we’re trying in some ways to limit some activity, and we’re trying to provide a safer environment for the New Zealand  public going onto the Internet in the first place.”

The DIA’s Web filter uses Whitebox, a system devised by Swedish company NetClean. The system blocks access to  sites on a list of identified sources of child sexual abuse material.

ISPs which opt to use the DIA’s system would hook up to what O’Brien calls a “secure tunnel” through which the  ISP’s traffic would be filtered. Anyone whose Web browser tried to access a listed site would be denied access and  would be told that the site contains objectionable material. If they think the system has made an error, they can ask for a review.

“This is only a very small part of our actual work,” he explained. “Our focus has always been on detecting people who  distribute and make or possess child sexual abuse images and the vast majority of our time is spent carrying out investigations.”

At the time the system was being tested by a group of ISPs, it was estimated that as many as 7000 Web sites were on  the DIA’s ‘blacklist’. O’Brien says that list will have to be rebuilt once filtering proper begins, but he believes the  number of sites has “dropped off quite significantly” since – not least because filtering systems have been implemented  in other countries.

O’Brien also rejects claims that anyone trying to access banned sites – deliberately or accidentally – will have their  Web address noted for followup inquiries. The user’s address, he says, is anonymised. The DIA keeps no record and  the ISP won’t know that their customer has tried to go somewhere illegal.

“We didn’t want to become a monitoring tool,” he said. “If the person concerned thinks it is a legitimate site, they can  bring it to our attention and we will check it as quickly as we can.” O’Brien also says the chance of an innocent site with the same URL as a blacklisted one getting blocked would be “extremely rare, and we do go over the sites time  and time again to ensure we have got them correct”.

Those who object to their ISP filtering sites can always change to one that doesn’t, but as O’Brien points out, since the  blocked sites are already illegal, why would they bother?

Bloggers also question why the DIA refuses to publish a list of banned sites, given that movies banned by the Censor  are a matter of public record. O’Brien responds that if the sites’ names were known, “individuals may try to access  those sites”. The Ombudsman’s office is investigating a complaint about this.

It seems the filtering system is unobtrusive (unless you try to go somewhere on the banned list). TelstraClear, one of the  ISPs that took part in the trials, says the process was “efficient and effective... with no disruption to traffic” and it intends implementing the system when it is ready. As for the critics, the DIA is planning to release a code of practice for Web filtering and wants to establish an oversight committee for the whole process. O’Brien is especially keen that  those who have questioned filtering should be part of that committee.

“The feedback we got was that overwhelmingly the New Zealand public were in favour of any measure that would give  them a safer environment and try to prevent further access these types of sites,” he said. “It’s a no-brainer really –  it’s no thin edge of the wedge into censorship at all, and we’re continually telling the ISPs and the New Zealand public that very fact.”