In any judicial system that uses precedents (or any other variation of common law), law reporting becomes vital to maintain consistency across the system. Say, for instance, that a judge or magistrate makes a particular decision in case X. This decision, and the argumentation behind it, needs to be accurately conveyed to other judges or magistrates across the land so that they can use similar reasoning and make similar decisions in cases that are similar to case X. If that doesn't happen, then different judges might make a drastically different rulings in cases that are very similar, which would create confusion about the meaning and application of law everywhere. This would have a deleterious effect on society as a whole, since no one could be sure what results they might get out of the legal system.