Free legal research can be conducted on these three websites. While these sites do not research as far back as Westlaw and LexisNexis, all provide links to federal and state case law, but each has some advantages and disadvantages which are discussed in detail. LesixONE has the option to jump to LexisNexis (with a credit card) for further detail.
"Using the Web for Free Legal Research: A Comparison of Findlaw, Lexisone, and the Legal Information Institute Websites,"
Marquette Elder's Advisor: Vol. 5
, Article 13.
Available at: http://scholarship.law.marquette.edu/elders/vol5/iss1/13