WestlawNext Advanced Search Glitch (?) — Implied Boolean OR in "All of these terms" Phrase Searches

As law school librarians gear up for the new academic year after the recent roll-out of WestlawNext to the legal academy, some matters are being raised that weren't readily apparent during the brief trials TR Legal had offered earlier. Here's one republished from law-lib with the permission of the author, Lee Ryan, Senior Reference Librarian, Univ. of San Francisco School of Law, Dorraine Zief Law Library. [JH]

I've come upon what seems to be a glitch in the WestlawNext advanced search template.  It has to do with using more than one phrase in the "All of these terms" textbox.  I've already passed this to West, but thought that others might be interested.

Here's what happened:

Seeking law articles that contained BOTH of phrases "omar khadr" and "optional protocol," I browsed to "Law Reviews and Journals,"  and clicked the "advanced search" link.

I then entered the following string in the "All of these terms" text box:

   "omar khadr" "optional protocol"

My results:  2746 documents.  Most of the results I looked at seemed to have "optional protocol," but not "omar khadr." It seemed as though WestlawNext took my space to mean "OR."  (And indeed, when I entered "omar khadr" "optional protocol" in the "Any of these terms" textbox, I got the exact same result: 2746 documents.)

Thinking that I was getting very odd results for an "All of these terms search," and suspecting my terms were being "or-ed," I switched to "classic" Westlaw, selected Journals & Law Reviews (JLR), and ran this Terms & Connectors search:

   "omar khadr" OR "optional protocol"

My results:  3031 documents.  (As a cross-check, in JLR I ran the Terms & Connectors search "omar khadr" AND "optional protocol" and got 23 documents.)

Back in WestlawNext's advanced search, I tried to use the "Term frequency" function to ensure that my results would contain both phrases. Asking that each phrase appear once generated this string, again in the "All of these terms" textbox:

   ATLEAST1("omar khadr") ATLEAST1("optional protocol")

But yet again, I got 2746 documents.

Finally, on the suggestion of our excellent Westlaw academic representative, I replaced the space between terms with the "AND" connector, and entered this in the "All of these terms" textbox:

  "omar khadr" AND "optional protocol"

Only then did I get the 23 articles that I had been expecting to retrieve.

I ran into this glitch only when entering phrases into the "All of these terms" textbox.

Searches worked as expected with single word terms. So, in the search:

   malpractice femur

the space was taken to be an "and"

And searches worked as expected when I entered a single phrase (such as "omar khadr") in the "All of these terms" textbox.

In sum, this strikes me as a non-trivial flaw in the WestlawNext advanced search engine.

The very words "All of these terms" clearly imply a Boolean AND, and there is nothing to suggest that using phrases in quotation marks will not work.

Further, advanced search templates of the major commercial search engines (Google, Yahoo!, etc.) all have an "all these words" function in which the Boolean AND is implied -- even when multiple phrases, each in quotation marks, are entered, -- which then sets up WestlawNext users to expect the very same functionality from "All of these search terms" on WestlawNext. 

Reading spaces between phrases in quotations marks in "All of these terms" searches will give researchers results that are exactly the opposite of what they have been lead to expect, both by Westlaw, and by their experiences in other search engines.

-- Lee Ryan, Senior Reference Librarian, Univ. of San Francisco School of Law, Dorraine Zief Law Library