Was the computer scanned then? So what's all this argument about whether the porn actually existed...?

The policeman was of the opinion that the porn was legal, so your "no case to answer" point falls as that was the position all along, and the policeman knew it. The possession of legal porn was never going to be a court matter so I don't see your point. As for holding "evidence" for nine years, I don't see that nine seconds, nine months, nine years or ninety years has any bearing on the legality or not of having that evidence. And do we know in what form the cop has been holding the evidence? Screenshot? Memory stick? Recollection? As far as I know, we haven't been told. And you haven't yet told us what bit of the Data Protection Act has been breached. The police seize private computers looking for evidence all the time. Someone had better tell 'em about that act...