The NYTimes reported on a fairly new phenomena in Supreme Court jurisprudence -- the case of link rot.
"Supreme Court opinions have come down with a bad case of link rot. According to a new study, 49 percent of the hyperlinks in Supreme Court decisions no longer work. The problem is that "[t]hose citations allow lawyers and scholars to find, understand and assess the court’s evidence and reasoning."
Wow! Nearly half of the hyperlinks no longer work, and the problem is bound to get worse as the links age. "Links in Supreme Court opinions are less likely to work as they get older. But even some recent links are broken. A decision from February, for instance, included a citation to statistics from the Ohio court system; the link leads to a dead end."
Again, this is a fairly new problem. "For most of the Supreme Court’s history, its citations have been to static, permanent sources, typically books. But "[s]ince 1996 justices have cited materials found on the Internet 555 times, the study found. Those citations are very often ephemeral."
"The Supreme Court has taken modest steps to address the matter. Its opinions note the date each site was last visited, and its clerk keeps a hard copy of those materials. The United States Court of Appeals for the Ninth Circuit, in San Francisco, could serve as a model. It maintains an electronic archive of what it calls “webcites” in the PDF format."
"Professor Zittrain who teaches law and computer science at Harvard and his colleagues are at work on a more ambitious solution, Perma.cc, a platform built and run by a consortium of law libraries. It allows writers and editors to capture and fix transient information on the Web with a new, permanent link. The project is initially focused on legal scholarship. And there is no reason, Professor Zittrain said, why it could not also work for the Supreme Court."
This is an interesting problem with the transient nature of websites -- especially as more and more authors rely on Internet sources. I currently work as the library liasion to both a law review and a law journal, and this is an issue for them, as well. They need to verify the sources that an author of a scholarly article cites, and in many instances, by the time the students access the cited websites, the links to the websites are already broken. I have recommended permanent archival websites akin to Perma.cc, but they have not made the jump. They are currently relying on PDFs like the Ninth Circuit mentioned above.
It is hard to stay on top of these things after the fact. Constantly updating links to websites amounts to another full-time job. As the Supreme Court is finding out, it is much easier to create a permanent link or a PDF archive while an opinion is being written and the information is still readily available.