There are two threads about this. The other one is (or was yesterday, haven’t looked yet) very contentious. The number of people tacitly supporting that just “looking” at child porn should not be illegal makes me want to vomit and leave FR.
Some made the excuse that people can get loaded up with child porn accidentally but to me that is just an excuse. As you noted, there is a gulf of difference between accident and purposeful intent.
I have an issue with going after someone unless you can prove they deliberately sought child porn. People do end up in a lot of websites they wouldn’t have chosen. Having an image or two in the chache is far from proof of intent to seeking child porn.
I don’t think FR people are wanting to allowed people to view child porn, so much as they are concerned with going after people who didn’t seeking child porn but ended up finding a picture by accident.
That said, claims of a virus downloading child porn into a computer are suspect at best. I have never heard of that happening. I’ve had more viruses than an african brothal, (I’m very risky online), but never one that started downloading files.