Updating a citation is difficult with government websites. Additionally, the code is only as current as the latest official print version. The rest had not been updated since January 5, 1999. The website has no suggestions about how to update the code sections. Only experienced researchers will think to look for more recent statutes on Thomas, the website from Congress.
Case law is even more problematic.
Cases older than 1990 are generally not available through free Internet sources, with the exception of U.S. Supreme Court cases. Additionally, cases on free websites lack editorial enhancements such as headnotes and links to items cited within each document. Also, these sites do not have an updating system that is as easy or accurate as commercial citation checking services, such as Shepard s or Keycite. For those willing to pay a small fee, there are several commercial publishers that use the Internet to compete with Westlaw and Lexis. As of this writing, each of these systems is much cheaper than the two major competitors.