Well back then, even though there was plenty of videos going round of that stuff to buy, it was made in countries where it was legal to do that stuff, the Internet was still a little bit wild westy, so unless you got caught with the kid shit, no one really cared about the porn you were downloading. Once it became more well known that people getting caught with pedo stuff had rape videos and beastiality videos in their collections aswell, they thought there was a link between going from normal porn, to animal porn and rape videos, then to pedo porn. So to try and stop it, they made it illegal to download "extreme" porn. I'm just going off of memory for all of this, but I think it fell under the misuse of computer act that they made the same year. So basically, they did this, but there was a clause that if you had any material where you could prove you had it before 2007, you wouldn't get in trouble for it because it wasn't illegal to own when you got it, but anything after, you were in the shit.

Even today you can still buy animal sex dvds from company's that sell mail order. They won't advertise it, you have to be buying stuff from the same company for a while before they send you their "explicit" collection magazines. These companies have been doing this same tactic for almost 40 years back when porn was all VHS.