Tonyblack said:
I can understand how someone might stray onto such a site (although one would have to be searching dodgy sites in the first place
)
but to actually download it is just asking for trouble.
OK not justifying this at all as I have no knowledge as to what happened in the case referred to but this is a technical response as Tony has made the same basic mistake that a lot of people outside the IT industry do about 'downloading an image'.
If you have seen it on your screen then you have downloaded it, the only way an image will appear is if it has passed from the server to your PC which is why some pictures fail to display and you have to refresh i.e. re-attempt the download. You do not have to decide to download anything, it is on your computer if it was ever included in a webpage you visited even if you never saw it because you didn't scroll down far enough to see it or it was off the edge of the visible page. This is what is in your cache for your browser and this is included in what is regarded as downloaded images.
'Straying' onto a site will automatically download images to your cache without you choosing to do anything and even if you immediately close the browser as soon as you realise then the images are there on your PC. Clearing the cache doesn't have any real effect on this as the files are recoverable and therefore regarded as 'images you attempted to delete'. Straying onto a dubious but not necessarily illegal site is also remarkably easy, a lot of dodgy sites are one letter away from the site you actually wanted, just try misspelling a few sites and see what you get, actually don't try misspelling a few sites you almost certainly won't like what you find as a lot of them are fakes to download viruses or other nasties rather than unpleasant or illegal images.
As I said at the start this is in no way a justification however I feel I need to correct the impression that you actually have to do something to get a picture on your computer