You can create a "virtual corpus" by selecting texts from among the 32,000 Supreme Court decisions. You  can use any of the criteria shown to the left to determine what texts will be in the virtual corpus. All of the criteria are optional -- just use those that you want.
 

At some point (hopefully soon), we will integrate the Supreme Court Database into this page (and hence the Virtual Corpora). Using that information, you would be able to search by chief justice (Warren, Rehnquist, etc), whether the decision was later overturned, which justices supported or dissented from the opinion, and so on.

Note that via this search form, you can only enter one single word in the [WORD] field. If you want to do more complicated searches with multi-word strings, substrings, lemmas, grammatical constructions, etc then you should create a virtual corpus using keywords. See the instructions by clicking on TEXTS/VIRTUAL in the search form, and then "Keywords in the Text" (the first link in that help file).

After you've created the corpus, you can add or delete texts and make other modifications to the corpus. You can also search just within the virtual corpus that you've created; you can compare the frequency of words and phrases across your different virtual corpora; and you can generate keyword lists from any of the virtual corpora.