Back in 2004 BT surprised the world when it announced Cleanfeed, a mechanism for restricting access to urls known to contain child abuse images. Not long after that Pennsylvania wanted to mandate local ISPs to deploy filters. One of the free speech groups opposed this and took the State to Federal Court. Part of the group’s objection was that filters tended to overblock so there was a risk of unintended, unwarranted and therefore unjustifiable censorship.
However, the whole point about Cleenfeed was its pinpoint accuracy. It could block the identified url with no danger of overreach. The Attorney General of Pennsylvania had heard about Cleanfeed and asked BT if it could have a copy of the plans to produce in court to prove how blocking could be achieved without any injury being done to legitimate free speech interests. BT declined to co-operate on the entirely understandable grounds that publishing the technical details of their scheme in open court would simply help the wrong people find ways around them (even quicker than they were likely to do anyway). The Attorney General’s office contacted me to see if I could get BT to budge. I couldn’t. Pennsylvania lost the case.
It has happened again. FBI agents have found a way to disentangle the TOR network to identify individuals who were swapping or downloading child abuse images. They brought a case against Jay Michaud and at first instance secured a conviction. However, in an appellate court the judge asked the FBI to show how they had obtained their evidence. The FBI will not do that so they have dropped the action.
I fully appreciate the dangers of justice going behind closed doors but, equally, there should be scope for prosecutors to disclose their methods to an appropriately qualified, sceptical judge i.e. one with technical knowledge or one who has technical knowledge readily available to her or him. After all, the only point at issue is whether or not the chain of evidence holds up to prove beyond all reasonable doubt that it was the accused and nobody else who did the particular acts and that the evidence has been properly obtained.
Bad hackers and other crooks will do quite enough damage without the courts giving them a helping hand.