That entirely depends on the patent. I could have a claim on a patent for the "method of obtaining answers via internet forum posts", and my lawyers could be sending you threats right now
Holding a patent on an entire category of product -- like a car, or a legal simulation -- is very rare. Usually patents cover smaller details, such as the way that you represent legislation within your system, etc... I just brought it up as copyright and trademarks are not an issue for your example, only a theoretical mega-patent (which might not even hold up in court) could affect that situation.