The number of suicide watch incidents in Louisiana prisons increased by 30 percent on extreme heat days, a recently published study in the JAMA Journal found. Researchers from Emory University analyzed data from 2015 to 2017 to examine how the heat index related to suicide watch incidents in six prisons. At the time, only one had air conditioning. 

Scientists classified days into six categories according to their average heat index, and also created an “extreme heat indicator” for those that were hotter than 90 percent of the days. The number of people put under suicide watch increased 36 percent when the heat index was above 90 degrees and 30 percent on the extreme heat days, which in most cases were even hotter. 

The study adds to the body of research that has found a link between suicide and hot weather, but also to new research on prison mortality and climate. 

“It’s so novel, and I am very excited that it is being published in a medical journal,” said Grady Dixon, a climatologist from Fort Hays University who  didn’t participate in the study. “Any shortcomings the study can have are just minor compared to the widespread impact this paper can have just by publicizing this issue.” 

Scientists have consistently found that unusually hot weather is often associated with suicides and other adverse mental health outcomes. 

“That word ‘unusual’ is really important because it’s not just hotter weather equals more suicides,” Dixon says. The days that are warmer than expected, even if they happen during winter, are the ones with the biggest spikes, he said. 

Although there is still no clear explanation for this, some scientists believe it is related to how warm weather negatively affects sleep. 

In March,  another  study by authors at Brown, Harvard and Boston universities found suicide rates in Texas prisons increased 23 percent the days after an extreme heat event. 

But the  Emory study uses another variable: suicide watch incidents, when correctional staff puts someone under observation because they fear they will kill themselves. 

Although not every person put on suicide watch commits suicide, it’s a measure of the distress that happens during heat, said David Cloud, the study’s lead author and a Ph.D. candidate at Emory. 

Julie Skarha, an epidemiologist from Brown University who co-authored the March study and didn’t participate in the Louisiana research, said the work was “so important because it’s another element of how heat is affecting people’s health.” The study also highlights the fact that people with mental health problems are overrepresented in prisons, which makes them more vulnerable to the heat’s adverse effects on mental health. “Prison is stressful enough, and then you add this layer of heat that people are powerless to escape,” Cloud said.

Heat in prisons has been a matter of litigation for Louisiana, and other states, since at least 2013. That year, the Promise of Justice Initiative represented several people who faced mental and physical health consequences from being exposed to seasonal heat in one Louisiana prison.

 In 2014, another group filed a class-action lawsuit against the Texas Department of Criminal Justice over the lack of air conditioning in prisons.  

This summer, during record heat waves, prisoners’ families rallied outside the Texas Capitol to protest the heat conditions in prisons. The Texas Tribune reported at least nine people died of cardiac events in uncooled prisons during the summer, and there have been 28 suicides in all prisons this year, according to data from the Texas Justice Initiative. Much like with Covid, the climate crisis is going to exacerbate any existing issues inside the prison walls, Cloud said. 

For him, it is “baffling” to see how much money states spend on litigation cycles instead of on implementing the air conditioning that prisons need. “We can all see the problem, we can all feel the problem,” he said. “But why don’t we use our money to do something about it rather than fight?”