It’s a mysterious diagnosis many in the medical community don't recognize, but police do.
Law enforcement and medical examiners in Jacksonville have used excited delirium syndrome to explain the deaths of several people in police custody.
Some call it a cover up for police brutality.
A Florida Department of Law Enforcement training manual said the signs of excited delirium include unbelievable strength, imperviousness to pain and bizarre behavior.
It's the same syndrome listed as the cause of death for Jacksonville father Paul Testa.
The schizophrenic inmate, whose charges had just been dropped, became unresponsive after being Tasered and strapped into a restraint chair at the Duval County jail Dec. 21, 2015.
“My dad was in the bed, choked out so bad that his eyes were popping out of his head. I mean, I knew right there that he was gone,” said his son, Christian Testa.
Paul Testa's family took him off life support and is now suing the Jacksonville Sheriff's Office.
Testa is one of eight people in Northeast Florida in the past five years to have excited delirium listed as a cause or contributing factor of death.
“It's oftentimes used for times when somebody dies and they can't pinpoint the exact nature of the cause of death,” said Justin Mazzola, an Amnesty International researcher.
Amnesty International is one of several human-rights organizations questioning whether excited delirium is a cover-up for police brutality.
“So it's basically a catch-all and it basically excludes other uses of force,” Mazzola said.
[ Story: Action News Jax investigates JSO's use of force behind bars ]
“When is it excited delirium and when is it homicide? And that's the issue," said University of Miami neurology professor Dr. Deborah Mash, the leading expert on excited delirium syndrome.
It's a condition only recognized by medical examiners, the American College of Emergency Room Physicians and law enforcement.
The American Medical Association and the American Psychological Association do not recognize excited delirium as a diagnosis. The syndrome is not in the Diagnostic and Statistical Manual of Mental Disorders or the International Statistical Classification of Diseases and Related Health Problems.
“When is it recognized? Why are we talking today? It's recognized when a person is dead,” Mash said. “Many doctors have never even seen an individual in this condition. They don't present to their psychiatrist. They don't just go to the doctor and say, 'I think I’m in a state of excited delirium and I need some meds.' No."
According to Amnesty International's data, 23 percent of excited delirium deaths after police Tasering have happened in Florida -- more than any other state.
Taser International acknowledged in an email to Action News Jax that excited delirium syndrome is the second leading cause of Taser-related deaths.
FDLE’s lesson outline shows Florida officers are trained that the safest way to handle someone showing signs of excited delirium is to Taser and restrain.
“We do not know precisely whether or not restraint will be additive to the stress that the individual is already experiencing,” Mash said.
[ Story: City of Jacksonville responds to schizophrenic inmate's son's wrongful death lawsuit ]
Action News Jax asked JSO Director of Investigations and Homeland Security Ron Lendvay whether it's appropriate to train officers to restrain if we don't know whether it makes people with excited delirium more likely to die.
“We do know that restraining individuals leads to the de-escalation of conflict. So absent scientific evidence to the contrary, I think it's our best move at this point in time," Lendvay said.
“This is a medical emergency. And if you can't get the patient under control, how do you get them medical assistance?" asked Mike Bruno, JSO Director of Corrections.
While researchers continue to study how to keep people from dying of excited delirium, officers continue their policy of Taser and restrain.
In the meantime, family members such as Christian Testa are left to with more questions than answers.
In September, Action News Jax's investigation revealed that over a two-year period, JSO used a controversial restraint chair in half of all cases where a corrections officer used force on an inmate. Out of 267 reports, six of those people were noted as exhibiting symptoms of excited delirium.
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