Re: Why now?
It was dealt with at the time, by which I mean it was ignored.
While I'm at it, I'd suppose that files on the computer disk are labelled as belonging to dgreen or to dgreensecretary so you would be able to tell who did it, including the web cache.
As for what's legal or illegal porn, it may be only a few pixels difference but I expect that forensic investigators have file checksums to identify commonly available smut. Images may also include the publisher's name e.g. Playboy which you would expect to be legal.