This has generated some debate. Before going further – I’d like to note that in this particular case were talking about very specific filtering of one type of image – not general filtering of age inaaproriate content such as that which you can already purchase from some ISPs.

Proponents of filtering will note that accessing child sexual abuse images from New Zealand is an offence under the Films, Videos and Publications ACT 1993 – and a filter merely enforces that law. I recently saw some statistics that estimated 20,000 new images of this type are created each month. Behind each image is a child victim.  Of course, children were victims  of this abuse long before the internet - but the internet has facilitated an evolved business model where images are swapped and sold. Therefore people who view, trade and buy these images online are generating demand for them.

An effective filter would disrupt this trading.  I deliberately use the world ‘disrupt’ because I wouldn’t want to give the impression that filtering can stop it. Many images are traded within peer-to-peer networks which won’t be filtered.

An effective filter would also prevent people from accidently stumbing on this sort of content.  

The opponents of filtering have a number of arguments.

• Filtering adds another step (checking the URL) in the transfer of data on the net which invariably impacts speed. This at a time when we’re looking to increase internet speeds.  
• The filters invariably suffer ’scope creep’. They start out with a narrow focus, but once the technology is in place – other types of content are added. Even assuming that the filter only ever filtered ’illegal content’ - not all ‘illegal’ content is as easy to define as Child sexual abuse imagery.
• The filters can create a false sense of security.

I think the trial is important, and so is public debate about what level of filtering is appropriate for a country like New Zealand.

And I would sign off this post by noting there are other ways to fight this practice such as increasing the capacity of the DIA enforcement team and increasing penalties and/or increasing rehabiliation services  for offenders.