At least 41 people have died in the Lone Star State’s unairconditioned prisons due to heat-related or unknown conditions this summer, according to the Texas Tribune.

Even so, it’s hard to firmly establish how many have succumbed to heat-related illness, according to observers. That’s because TDCJ’s official stance is that no inmates have died of heat exhaustion since 2012 — the same year the agency began to be bombarded with wrongful death lawsuits from inmates’ families, the Tribune reports.