Several times this semester I have run into some people who are a bit confused about Westlaw's headnote and key number system -- and quite understandably! For something that is used so much, it seems that little attention is given to explaining exactly what is going on. Well, I would like to cure that right here, right now!
First, let's look at a headnote taken from the case Brown v. Board of Education, 347 U.S. 483 (1954).
> Constitutional Law k. 3278(1)
The doctrine of “separate but equal” has no place in the field of public education, since separate educational facilities are inherently unequal. U.S.C.A. Const. Amend. 14.
What we are looking at are actually two completely different things: the key number and the headnote. As I'm sure you already know, West's key number system was developed and is used to label different legal topics, making it easier to search case law. It uses a broad topic name (there are more than 450!) followed by a narrower number. It looks something like, "Constitutional Law k. 32878(1)" where "k" represents a tiny picture of a key.
Well to make things a bit more complicated, we also have headnotes. Headnotes are quotes taken from the case pertaining to an area of law and placed at the beginning in order of appearance. So the part of the case addressing "constitutional law, equal protection in general" would be one headnote, and "constitution or law of state contravening constitution of United States" would be a difference headnote. There is no uniform system of numbering with headnotes, so "constitutional law, equal protection in general" in one case may be headnote 4, while it's headnote 2 in another case. It really just depends where it falls within the case.
Now that West has the key numbers and headnotes all lined up for each case, searching out your area of law becomes easier. West prints off all of the topics and key numbers in a series of books called The Digest. The legal topics are in alpha-numeric order, and each jurisdiction has its own. Kansas has the Kansas Digest, and Missouri has the Missouri Digest. There are also regional digests that include cases from states within a set region. Under each topic and key number, you will find the headnotes from the cases. So if you are looking for other cases that touch on "constitutional law, equal protection in general," you would look up "constitutional law k. 32878(1)."
You can do all of this online if you desire. However, if you are looking online, "constitutional law" will be turned into a number, which just happens to be "92".
So where does "92" come from? Well, if you were to list all of the legal topics in alphabetical order and then assign it a number, "constitutional law" would be "92." Of course, I find it easier to grab any Digest volume and look at the front. The topics and their numbers are listed, starting with "1 abandoned and lost property" going through "414 zoning and planning." So "constitutional law k. 32878(1)" is the same as "92k.32878(1)." Or it usually is. But that's another story.
>Here is what the same headnote will look like online:
> KeyCite Citing References for this Headnote 92 Constitutional Law
92XXVI Equal Protection
92XXVI(B) Particular Classes
92XXVI(B)8 Race, National Origin, or Ethnicity
92k3278 Public Elementary and Secondary Education
92k3278(1) k. In General.
(Formerly 92k220(2.1), 92k220(2), 92k220) The doctrine of “separate but equal” has no place in the field of public education, since separate educational facilities are inherently unequal. U.S.C.A.Const. Amend. 14.
All of the extra information is showing you the Digest outline so that you get a feel for where you are. So "92k3278(1)" is constitutional law> equal protection> particular classes> race, national origin, or ethnicity> education> public elementary and secondary education> in general.
The key number system is proprietary. You will only find it in West products and on Westlaw. LexisNexis, though, has developed its own version, which works much the same. Unfortunately, there is no book version of Lexis' headnote system.
I hope this makes sense. As always, let me know if you need help!
Instructional and Research Services Librarian