Rule 645 A book, purporting to contain reports of cases adjudged in the tribunals of the state or nation where the book is published, is presumed to contain co…

When a published book of court cases is presented in a California court, the court will automatically assume the cases in that book are reported correctly. You do not need to prove that the cases were accurately written down.

This applies to law books that contain court decisions from the state or country where the book was published. For example, a book of California court cases published in California would be trusted as accurate without extra proof.