In APA style. Or, do you know any online resources explaining this? I can’t really find any.
Check out the Harvard Blue Book: A Uniform System of Legal Citation, 18th ed.. It’s got an introductory section on legal citation aimed at first-year students, who don’t have extensive knowledge of legal citation. You might find it helpful.
http://www.lib.jjay.cuny.edu/research/apastyle.pdf (pdf page 7)
http://www.lib.wsc.ma.edu/legalapa.htm
The Bluebook is used for legal documents and law-related publications (I use it every day). I don’t know how appropriate its conventions are for non-legal works.
The links say that APA format for legal citations is based on the Bluebook.
I don’t have a copy of the APA stylesheet here, but we had a thread a few weeks ago(?) that presented an interesting question:
In legal writing, a case is a case. APA format requires the writer to indicate a print source that is viewed online. What happens if you find a case on findlaw? Do you attribute it there?
An easy solution for anyone with access to a law library would be to simply check the cite against the printed version of the case. But if it’s in some obscure reporter, or if you don’t have a law library nearby, what then?