This could happen theoretically although there is not obligation to keep or even use such a logfile. Also I believe the police wil other priorities than hunting down individuals guilty of a copyrighted download. I would not worry so much about that aspect. The future of the site is something to keep in mind though. It may help that it is not a public site. If a publisher objects to their stuff being in this site they can only demad to remove it, not shut down the site (as I think was the case with IMSLP but the owner decide to shut down anyway).