Two lawsuits over sweltering conditions in Texas’s prisons are now working their way through the federal courts.

During last summer’s record heat wave that scorched Texas, at least four inmates died of hyperthermia or heat stroke behind bars, Manny Fernandez reported in Wednesday’s New York Times. The family of one of those dead inmates, 58-year-old Larry Gene McCollum, filed a wrongful death lawsuit in federal court in Austin on Tuesday. (McCollum was serving an 11-month sentence for forgery when he died last July, the Texas Tribune reported Tuesday.)

Another lawsuit, filed in 2008, has been appealed to the U.S. Court of Appeals for the Fifth Circuit. In that case, Eugene Blackmon sued the Texas Department of Criminal Justice after he said he suffered “headaches, blurred vision, and nausea” after being confined in a Beeville prison, the Garza East Unit, where the indoor heat index reportedly reached 134 degrees.

“The Constitution doesn’t require a comfortable prison, but it requires a safe and humane prison,” Scott Medlock of the Texas Civil Rights Project, a group involved in both lawsuits, said. “Housing prisoners in these temperatures is brutal.”

Air conditioning in the Texas prison system is relatively rare: “Only 21 of the 111 Texas Department of Criminal Justice units are fully air-conditioned, TDCJ spokesman Jason Clark said. The remaining 90 are partially air-conditioned, usually in the medical or education area of the unit rather than the housing area,” according to the Texas Tribune.

These unairconditioned conditions exist thanks to a peculiar quirk of Texas law that “requires county jails to maintain temperature levels between 65 and 85 degrees” but does not impose the standard on state prisons, Fernandez reported.

Gawker‘s Hamilton Nolan was horrified at the news: “Four (4) (FOUR) Texas inmates died from the heat last summer. Four. Dead. That is a problem,” he wrote.