FLITE (Federal Legal Information Through Electronics)
Supreme Court Decisions 1937-1975. This system, on GPO's Fdsys website, contains the full text of U.S. Supreme Court Decisions (U.S. Reports, Volumes 300-422). Cases are searchable by case name and full text.
Decisions are available as ASCII text files that can be read on your browser's screen or saved to your hard drive and accessed using most word processor programs.
You may use the Full Text Search option, but beware that the size of the database and the number of words (14.5 million) may require more than one search to find what you need.