Valley fever, caused by inhaling fungal spores, is particularly prevalent in certain California prisons. (It’s unclear why.) Dozens of prisoners sue, claiming their increased exposure risk violates the Eighth Amendment. And black prisoners—who are more likely to get the fever (it’s unclear why)—claim they weren’t kept out of those prisons soon enough. Ninth Circuit: Qualified immunity. Prison officials tried to mitigate exposure risk, and besides, people do voluntarily live in places with increased risk of valley fever. As for the black prisoners’ claim—prison officials couldn’t know the Constitution required them to discriminate. (A further detail: Because of other problems, California’s prison medical system has been under federal control since 2006.)