Graphics of Legal Research – Part 2: Depth Analysis or: Don’t Get in Too Deep!

When conducting legal research in Westlaw, Lexis, and Bloomberg Law, you will encounter a number of graphics and symbols that are simultaneously helpful and confusing. In this three-part Graphics of Legal Research series, we are going to demystify some of the most common graphics that you may encounter when conducting legal research:

Part 1 – citator symbols
Part 2 – depth analysis
Part 3 – Ravel Law

Lexis shows how deep into the case one must read to find references to the authority in question. A depth bar with four blue boxes will be more likely to be relevant to your research than one with fewer colored spaces. Cases and statutes may be merely mentioned and not discussed in depth in opinions, so paying attention to the color bars will help you find useful analysis without wading through irrelevant cases. It’s a good, but not foolproof, way to research efficiently without spending undue time on irrelevant case law.

  • Open the case you want to research further.
  • Click on “Citing Decisions” at the top of the page.
  • Citing references are arranged by courts, with cases from the same jurisdiction as the authority being examined at the top.
  • Find the depth graphics below the names of the citing decisions.

Westlaw provides depth tools in its “Citing References” tool in legal materials. A depth bar with four green boxes will be more likely to be relevant to your research than one with fewer colored spaces.

  • Open the case you want to research further.
  • Click on “Citing References” at the top of the page.
  • Citing references are arranged by the nature of the treatment of the authority you are researching, with the most negative treatment at the top.
  • Find the depth graphics at the right side of the screen.

Bloomberg Law also includes depth signals, with a ranking out of five instead of Lexis’ and Westlaw’s four. However, it functions much the same.

  • Open the case you want to research further.
  • Click on “BCite Analysis” along the right side of the opinion.
  • Open “Citing Documents.”
  • Find the depth graphics at the right side of the screen, next to the case name.

Andrea Gass, Reference Librarian