smiddy3, that's what the brochure Who Are Doing Jehovah's Will Today? (2014), which Jehovah's Witnesses currently use in Bible studies, says on the page titled "How Can the Kingdom Hall Library Benefit Us?":
"You may be able to make good use of the Kingdom Hall library when preparing your assignments. The Life and Ministry Meeting overseer is in charge of the library. He is responsible for making sure that the latest publications are there and that they are well-arranged. He or your Bible teacher can show you how to find the information that you need. However, no books should be taken out of the Kingdom Hall. And, of course, we want to handle the books carefully and not make any marks in them."
https://www.jw.org/en/publications/books/jehovahs-will/kingdom-hall-library/
This was the policy at at least one of the halls I studied, I know that because one of the Brothers I met who called himself a "maverick" just snuck one out the door when he wanted to read it, haha, I respected that.