Howard Bashman comments here that it's time to abolish invisible rulings by state appellate courts, and he's right.
The Virginia Supreme Court is, to my knowledge, one of the very worst offenders on this point - it is impossible to find on Westlaw or online an unpublished decision, even though the lawyers in the case get them from the clerk (and the Richmond law firms get them the same way).
One of the cases I argued before the Virginia Supreme Court is unpublished, might as well have never been decided. And, it was an interesting case, even though my side lost.
By contrast, the unpublished opinions of the Virginia Court of Appeals are in a sense published on the website and on Westlaw - even if they cannot be cited as precedent, everyone can read them. Access to unpublished opinions is an open government issue.