A few days ago a member who I wont name got banned for posting a link to a ROM site. If the thread was not deleted within a certain time frame would Costello potentially face criminal charges? Could Costello press criminal charges against this member? It would be quite exceptional for criminal charges to arise. I just want to know if it is possible, as unlikely as it is.
Who knows.
The server I think is still in France, Costello is not in France these days.
In this case we now get international law involved, plus wherever the member might have been at the time. Such things are hideously complicated most of the time. I imagine though legal problems would only really arise if after proper notice has been served that things are not removed within a reasonable timeframe.
Most individuals don't press criminal charges, such things are left to nation states/governments, though you can of course report things to the relevant authorities for them to consider. Civil charges would be most individuals are reasonably able to do.
Depending upon where it all goes down then site owners might be able to use some kind of safe harbour provision, though this gets tricky and the recent case involving livejournal
https://www.eff.org/deeplinks/2017/04/ninth-circuit-sends-message-platforms-use-moderator-go-trial http://cyberlaw.stanford.edu/blog/2017/04/bad-news-livejournal-bad-news-dmca-safe-harbors-post-1-3 might play into things here.
Before all that though you risk getting blacklisted, ad companies don't want to work with you, neither will PR firms, people then don't link to you and if the blacklisting was not bad enough then the "more links, more better" thing most ranking engines use these days take a hit.
A generally good rule in life though is never interact with the police or courts if you can help it. Lawyers are an expensive hobby to fund and such funds are typically better spent on servers, prizes, review items, going to events and such.