I would have thought that this could be challenged under the 14th Amendment (https://en.wikipedia.org/wiki/Due_Process_Clause). "Due process" must surely include being able to find out what laws might apply to you, and a paywall would seem to breach that.
I can't believe this is still coming up in this thread, but reading the other comments one learns that the laws are available to read you just can't publish them because a private company has that contract.
Here's the link, read away:
http://www.lexisnexis.com/hottopics/gacode/Default.asp
Edit: Also, I didn't realize this was a dupe until I responded. This discussion already took place.