I'm not a law librarian, so take my answer with a heap of salt.
Looking at appendix 7.1 of the APA style manual it appears that you could go with example 3. Sample reference to an unreported decision:
Gilliard v. Oswald, No. 76-2109 (2d Cir. Mar. 16, 1977).
Explanation: The docket number and the court are provided. The opinion was announced on March 16, 1977. To cite to a particular page of a slip opinion (opinion that is not published in a case reporter but is separately printed), use the form slip op. at [page number]. (American Psychological Association, 2010, p. 218)
I am not certain on this, however. The APA style manual suggests two sources to consult when making legal citations: The Bluebook: A Uniform System of Citation and law librarians. If you aren't familiar with the Bluebook here is a guide that looks like it should be useful. I can also check with a professor I know in a law school, though you'll have to wait until Tuesday for me to be able to do that.
Edit: I managed to talk for a few minutes to the law professor. She was busy, which means I didn't get every question answered, but I did learn some from her. She confirmed that the APA style rule quoted above would be the one to use if the cases aren't printed in a reporter. That led to a digression about how very few cases from lower courts actually get published. She also recommended the guide to the Bluebook I linked above as well as this guide by Cornell University's Law School.
Between what the law professor said and what the APA Style manual had to say, it looks like you should probably include the electronic database you found the documents in. This would go in parentheses at the end of the citation. I'm not entirely sure on abbreviations, but this is how the database I found the documents in might be cited: (FDsys, US Courts Opinions, Dist file).
I also took a look at the Bluebook, though the edition I managed to find was the 17th edition and not the current 19th edition (sometime this spring/summer the 20th edition will be published). So the information I found may or may not be current depending on what was updated between editions.
Section 10.8.3 on Briefs, Records, Motions, and Memoranda of the Bluebook seemed relevant:
Use the designation given on the document itself, followed by a full citation to the case to which it relates. Indicate the docket number parenthetically:
Appellant's Opening Brief at 5, Rosenthal v. Carr, 614 F.2d 1219 (9th Cir. 1980) (No. 76-1917).
Brief of Amici Curiae Alabama Law Foundation, Inc. et. al. at 5-6, Phillips v. Wash. Legal Found., 524 U.S. 156 (1998) (No. 96-1578).
(Harvard Law Review Association, 2000)
Section 10.7 on Prior and Subsequent History of the Bluebook also seemed like it might be relevant:
Give prior history only if significant to the point for which the case is cited or if the disposition cited does not intelligibly describe the issues in the case, as in a Supreme Court "mem." Give separate decisions of other issues in the case with their prior and subsequent history only if relevant.
10.7.1 Explanatory Phrases and Weight of Authority
(a) Prior or Subsequent History.
Append the prior or subsequent history of a case to the primary citation. Introduce and explain each decision with italicized words between each citation.
Cooper v. Dupnik, 924 F.2d 1520, 1530 & n.20 (9th Cir. 1991), rev'd en banc, 963 F.2d 1220 (9th Cir. 1992).
(b) Significance of disposition.
give the reason for a disposition if the disposition does not carry the normal substantive significance.
vacated as moot,
(d) Multiple Dispositions.
Multiple dispositions following a primary case citation should be connected with the word "and" in italics:
United States v. Baxter, 492 F.2d 150 (9th Cir.) cert dismissed, 414 U.S. 801 (1973), and Cert. denied, 416 U.S. 940 (1974).
(Harvard Law Review Association, 2000)
I hope this is enough for you to cite the documents in question. I would still recommend you double check with a law librarian to make sure you are citing correctly. If you don't have a law librarian easily accessible, you can try asking the reference librarians at the University of Washington, at Cornell University, or at the law library of your choosing.