when their archive scrapes posts from here, it will know if/when a post is deleted, but not necessarily why. even if it was illegal content, the archive will not know the difference, and the archive ends up unwittingly hosting a lot of illegal content. most of it fits within criteria by which the archive will allow you to search. deleted posts are one of those criteria. archives can counter some of this by not storing images of certain hashes or certain keywords, but there are obviously ways around this, and a lot of the stuff just gets buried, though it can still be fetched quite easily if you know how to search for it. even with moderators who will actively search for and remove illegal content, that 1: obviously still won't catch everything, and  2: introduces a complication on their end of admitting that they're storing "bad shit," with no recourse if law enforcement ever gets involved. what would they say to the cops? "we can't be held responsible, we get all of our stuff from 4chan." at best, cops can't do anything, at worst, the cops would just force them to shut the archive down. this is the next best move as they see it. they put up a warning, and maybe detect what ips are searching for what criteria, and block them, while still privately scrambling to delete whatever illegal stuff they haven't yet caught. no need to get police involved, no need to determine the "intent" of the users, because they can ban any ip for any reason. > tl;dr, this is culpable deniability 101, and their effort to deal with a problem in-house.
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