Just a few days after posting, my chart is out of date. On May 2, the Oregon Senate approved a bill authorizing same-sex domestic partnerships (link via Towleroad). Since the Oregon House has already approved it, and the governor is expected to sign, I ought to add another line to my chart:
|2007 Oregon||1844 Oregon|
To be consistent, actually, I should add in the right column all the states and territories that outlawed slavery between “1818 Illinois” and “1844 Oregon.” In other words, no sooner did I wonder why the pattern I’d noticed hadn’t yet “been broken by the passage of gay-union laws in states like California, low in the right column not because they abolished slavery later but because they didn’t exist until later,” than Oregon broke it for exactly that reason.