Stifling heat at a Miami-area concrete prison without air conditioning contributed to four deaths and subjected prisoners to cruel and unusual punishment, according to a federal lawsuit filed Thursday.

Three Dade Correctional Institution prisoners, represented by the Florida Justice Institute, said in the class-action suit that the state facility’s heat index surpasses 100 degrees in the summer. Prisoners are “routinely treated” in the infirmary for heat rashes, heat exhaustion and related illnesses, the lawsuit said, before they are returned to the “dangerously hot conditions” that sickened them.

Florida Justice Institute attorney Andrew Udelsman told USA TODAY the nonprofit law firm has received a rising number of prison heat complaints over the last decade.

“In Miami-Dade County, it’s considered cruelty to animals to leave a dog in a parked car in the summer,” Udelsman said. “And here, basically, (the Florida Department of Corrections) is incarcerating at this prison 1,300 people in these concrete boxes all summer along, and basically ignoring their pleas for relief.”

The Dade Correctional Institution and Florida Department of Corrections did not immediately respond to USA TODAY’s requests for comment.

The lawsuit comes as meteorologists warn of abnormally hot temperatures across the globe. In the hottest summer on record this year, researchers said people in prison were made especially vulnerable to heat-related illnesses – or death – in confined spaces often with no air conditioning.

A recent study at the Massachusetts Institute of Technology found more than 98% of prisons in the United States experienced at least ten days that were hotter than every previous summer, with the worst of the heat-exposed prisons concentrated in the Southwest.

Lawsuit alleges grueling prison conditions in summer heat

According to the lawsuit filed in U.S. District Court for the Southern District of Florida, most men in the 28-year-old prison suffer from at least one form of heat-related illness during the summer.

“Some have died of heat stroke or heart-related conditions that were exacerbated by prolonged exposure to extreme heat,” the complaint said.

The only air conditioning is in the officers’ control rooms, and plaintiffs said guards stationed in the dining area will rush prisoners to eat so they can return to the cooled spaces.

In a desperate attempt to escape the heat, the lawsuit said many prisoners wet their sheets and sleep on the concrete floor.

People in solitary confinement spend about 23 hours a day in hot, badly ventilated cells that are smaller than an average parking space, where they sleep, eat and use the toilet, according to the complaint. They are allowed a limited number of showers a week.

One person who spent months in confinement bathed himself with toilet water at night because it was cooler than the sink water, the complaint said.

The lawsuit comes after a disappointing legislative session in Florida for prison reform advocates. State lawmakers declined to consider several bills aimed at improving prison conditions, including legislation that would have made air-conditioning mandatory in every housing unit in all of Florida’s correctional institutions.

Extreme heat contributed to deaths in prison, lawsuit says

The lawsuit alleges that heat played a role in four deaths and the toll could rise as more information comes to light, Udelsman told USA TODAY.

One prisoner, identified as “J.B.” in the lawsuit, had complained for weeks of chest pains and difficulty breathing, the lawsuit said. The 81-year-old man was in a wheelchair, so he was assigned to a one-person cell, which had poor ventilation.

On Sept. 20, plaintiff Dwayne Wilson said he heard J.B. hollering for help from the cell. Wilson found him lying on the floor and gasping for breath, so he alerted a guard to the medical emergency, and J.B. was given breathing treatment before he was ordered back to his cell.

“The medical staff accused J.B. of coming to the air-conditioned infirmary simply to get out of the heat,” the complaint said. “Prisoners attempted to advocate on J.B.’s behalf, telling medical staff and officers that he was very ill.”

J.B. was found dead in his cell on Sept. 24. Court filings said the heat index reached 104 degrees that day – within the National Weather Service’s “danger” zone – and the exhaust fans in his cell were not working.

“It is likely that prolonged exposure to the hot, unventilated air at (Dade Correctional Institution) contributed to J.B.’s death,” the lawsuit said.

Plaintiffs say they fell sick from heat

The three plaintiffs named in Thursday’s lawsuit all said that they fell sick from heat in the prison this summer and “have exhausted all available administrative remedies.”

Wilson, 66, in August fainted in his dormitory on a day the heat index reached 100 degrees, according to the complaint. He was carried to a medical unit and administered an IV, and a healthcare provider told him to “stay as cool as possible.”

Another plaintiff, 54-year-old Tyrone Harris, said in the lawsuit that he had to be taken to the medical unit for a one-hour breathing treatment two to three times a week this summer. Harris has asthma and takes medication for high-blood pressure and cholesterol, which make him more susceptible to heat illness, the lawsuit said. He often gets heat cramps, heat rashes and feels lightheaded.

Court filings noted Dade Correctional Institution’s population is especially vulnerable to heat exhaustion as more than half are over the age of 50 and nearly 25% are over 65. Many prisoners have medical conditions or disabilities that increase susceptibility to heat illness.

Majority of US prisons don’t have universal A/C

A USA TODAY analysis in 2022 found at least 44 states did not universally air-condition their prisons and only one – Tennessee – said it was fully air-conditioned.

In Florida, about 24% of state prison housing units are air-conditioned, corrections department spokesperson Molly Best previously told USA TODAY. Fans and exhaust systems are used in lieu of A/C units.

People in prisons often face especially dire conditions when extreme heat hits as facilities are ill-equipped for blazing temperatures. And while some states aren’t typically known for oppressive heat, experts said they should be prepared for the realities of a changing climate.

“A lot of these prisons were not built to be comfortable or humane in the first place,” said Ufuoma Ovienmhada, lead author of the MIT study on prison heat. “Climate change is just aggravating the fact that prisons are not designed to enable incarcerated populations to moderate their own exposure to environmental risk factors such as extreme heat.”

Contributing: Jeanine Santucci, Javier Zarracina, Jennifer Borresen, USA TODAY; Elena Barrera, USA TODAY NETWORK – Florida