It's the law, combined with cases from Domstolsverket (Courts Administration). He has a tech description to:
I'll try to translate:
he fetches laws from the Cabinet Office web server, which he converts into XML (XHTML2 med RDFa)
He then retrieves cases from the Courts Administration FTP server, also converts this into XML. (via words "save as HTML", and then converting).
He then compiles all the meta-data from all the documents into RDF -graph. This is used in conjunction with style sheets to create XHTML1.0 pages, ready for displaying in a browser.
finally, indexes and Table of contents are created and the result is hosted on Apache-servers. The code is written in python, with parts in XSLT.
Impressive, impressive work. Which landed him a job in e-gov (I hope he keeps the law-project going!)