To flesh out my thoughts, there are publicly accessible law libraries you can go to for working through the up to date case law by checking the registers and what not, but from my understanding this is a far slower process than using the tools most practicing attorneys pay rather large recurring access fees to. If there is a lawyer about, feel free to correct me, but I believe Westlaw is one, LexisNexis is another I think? It's been a while since I was deep in this vertical of research. What I do remember is that the difference in efficiency between someone who does have access to one of those systems vs. Someone who doesn't is essentially the difference between someone armed with Google Case Law Edition vs. someone working out of a card catalog. You can get an order of magnitude higher discoverability leading to potential alternate avenues for legal construction with one over the other. You can also get an idea of what approach any defense or counterpart might make by researching what your opponent would want since you're both working out of the same b o st of case law.

If you're just looking to do one case and be done, the law library may work. If you're in court with any regularity, the rest of the profession has made your decision for you, and it's time to pony up for access to the big boy's toolset.