The Marshall Project has been investigating the effects of extreme heat on prisons and jails for nearly a decade. As ever-rising summer temperatures make this subject more urgent, our staff compiled a toolkit to help local reporters, researchers and policymakers do the same in their communities.
Our July 2026 webinar asked a slate of national experts for their best advice on how to explore the issue — and for the facts most people don’t know about how heat impacts incarcerated people. Their tips span the climate, criminal justice, public health and immigration sectors. Here are their key findings:
Look out for underlying conditions
Not every heat-related death is heatstroke, said Susi Vassallo, M.D., a certified correctional health professional and clinical professor at NYU School of Medicine’s emergency medical department.
“Although we think of heat as causing heatstroke or heat exhaustion, there are not nearly as many of those — in the free world or in prisons — as there are worsening of underlying conditions,” Vassallo said.
According to Vassallo, medical visits, hospitalizations and deaths all increase “precipitously” in hot weather, but most of those involve people with cardiac or respiratory diseases or other chronic conditions such as diabetes. While an autopsy or death certificate may not mention heatstroke or hyperthermia as the primary cause of death, there may be heat-related conditions listed as secondary or contributing factors. Requesting death records for people who died at an un-air-conditioned facility during a heatwave and running them by a medical professional can help determine whether heat was a factor in the person’s death.
Extreme heat can be more dangerous for people with chronic conditions in prison, Vassallo said, due to their inability to control the temperature of their environment and also because there is often less access to high-quality medical care to treat symptoms when they arise. Additionally, certain demographics can be particularly vulnerable, such as older adults or people in solitary confinement.
Interrogate so-called ‘solutions’
Officials may say they have numerous mitigation measures in place to keep people from overheating in facilities without air-conditioning, but not all cooling tools are created equal. Ufuoma Ovienmhada, an assistant professor at the University of Arizona’s School of Geography, Development & Environment and founder of the Toxic Prisons Mapping Project, pointed to research indicating that “above certain temperatures, a fan makes no difference” in reducing heat exposure — and in humid climates, can actually make the heat feel worse.
Fans are also rarely provided for free, Ovienmhada said, and at some facilities can cost the equivalent of months of work on a meager prison salary. Additionally, not all cells have outlets, meaning even if someone has a fan, they can’t always use it. Other potential sources of respite, like cups of ice or cold showers, are rarely offered.
This means that “incarcerated people often resort to extreme measures of either shedding their clothes or purposefully flooding their cells with toilet water to create basically a swimming pool to cool themselves,” Ovienmhada explained, but these “heat-adaptive behaviors” are frequently met with punishment. “These same behaviors that they’re doing just to survive can result in sanctions or even being thrown into solitary confinement,” she said.
Beware the cold
Heat emergencies aren’t the only example of dangerous temperatures.
“In California, the attorney general here actually sued Los Angeles County for its jail system, and their case concerned both extreme heat and extreme cold,” said Rio Scharf, staff attorney at UC Berkeley’s Criminal Law and Justice Center. He added that there have been at least two deaths related to hypothermia in the last few years.
Extreme cold is also an issue impacting ICE detention centers, Scharf said, with ongoing litigation in several states — including California — that aims to require blankets and warmer clothing in frigid facilities. In many of those cases, he said, “either the conditions [were] naturally cold, or the AC was being blasted to make people uncomfortable.”
In her research, Ovienmhada previously told The Marshall Project that she’s heard similar instances of air-conditioning being weaponized by corrections officers to punish or coerce people.
Know the litigation
There are three major legal arguments attorneys have used to assert that extreme heat constitutes a civil rights violation, according to Scharf. First is the Eighth Amendment, which argues that the impact of extreme heat — effectively cooking people to death — constitutes cruel or unusual punishment.
Second, in the case of local jails and ICE detention centers, lawyers have also presented due process claims under the Fifth and 14th amendments, arguing that people who haven’t been found guilty of anything shouldn’t be punished at all — which includes forcing them to bake in the heat (or freeze in the cold) with no relief.
Finally, there have also been lawsuits alleging violations of the Americans with Disabilities Act, which focuses on the ways extreme heat can be “especially harmful to people with pre-existing disabilities,” Scharf said.
However, because these laws require attorneys to prove not only that harm was done, but that it was the result of deliberate indifference by the local, state or federal government, Scharf noted that even when the legal arguments are strong, “these cases are really hard to win, and you can sometimes win without actually getting any relief.”
When in doubt, ask an expert
Legal documents and other related court records can be a goldmine of information describing how exactly extreme heat affects people in carceral facilities, said Maurice Chammah, staff writer for The Marshall Project. But court filings on yearslong cases can have hundreds of entries and it can be daunting to know where to start.
“Journalists shouldn’t be afraid to reach out to counsel in the cases and ask to be directed to documents that are going to be most useful to them,” Scharf said. In his own research into the impact of extreme heat on people in California jails, Scharf said he’s requested civil grand jury reports, grievances from incarcerated people and monitoring reports from any agencies that oversee the local jails, whether a state oversight office or an independent watchdog.
Chammah also recommended combing the federal court record database PACER for pro se litigation or lawsuits filed by incarcerated people during the summer months against their local sheriff. Though pro se lawsuits rarely result in legal action, they can serve as a real-time record of what was happening behind bars at the time of filing, as well as a blueprint for what sources to contact, since documents routinely mention cellmates, family or corrections employees.
It can also be helpful to seek out research related to how extreme heat intersects with your specific area of coverage. Here’s the full resource sheet from our webinar, which includes contact information for our expert panelists. We encourage journalists to use quotes from panelists in their reporting or follow up with any of the experts.