It isn't a left/right thing.

There was a case a while back where a woman poisoned her husband. The police found her thumbprint on a book on poisons in the library. I don't think they used library records, they just checked the book itself.

I also recall that there was considerable pushback from the librarians when the government demanded they hand over all borrower records.

Next time I go to the library I'll ask what the current state of this is. I hope their practice is to purge records when you return a book.