Ha...you posted this 11 minutes ago as of right now. 12 minutes ago I found a similar link citing Bluebook abbreviations and posted a "never mind, I figured it out note" (and mentioned I felt silly for not noticing it right away--I went to law school in Washington and so spent three years seeing "Wash." on the spines of case reports).
It took me 12 minutes to post because I tossed in some explanations for people not familiar with legal citations. As soon as I posted, I saw yours, and deleted mine as redundant.
There is one thing, though, that I discovered working on that post and am curious about now. I picked a case at random to use as an example, Peterson v. City of Seattle, 316 P.2d 904, 51 Wash. 2d 187 (1957).
Here's a link to the Washington Supreme Court's opinion:
Within the opinion they cite the case as 51 Wn.2d 187 (1957) at the top. Inside the opinion they cite some Washington cases as Wn and some as Wash. I could see no obvious patter as to which they pick.
Anyone happen to know offhand what determines which form they use?
For the jurisdiction slugs we use the standard legal citation abbreviations for each state:
https://law.resource.org/pub/us/code/blue/IndigoBook.html#T1...
This has the advantage of matching the citations to cases, like "123 Wash. 456".