© John Chapple/Rex FeaturesHandle with care
Rare as these deaths are, more often than not police brutality is blamed and officers are taken to court, but researchers now think that such events are the result of a rare disorder called "excited delirium".
Anecdotally, physicians use the term to describe a state in which a person becomes agitated and combative, with superhuman strength and skyrocketing body temperature. However, the American Medical Association does not recognise the disorder, which has led to claims that it does not exist and is merely an excuse used by police.
To investigate mechanisms that might underlie the disorder, Deborah Mash and colleagues at the University of Miami in Florida analysed brain-tissue samples from 90 cases of sudden death in which the person had telltale signs of excited delirium.
The team identified two biomarkers common to all 90 individuals (Forensic Science International, DOI: link). The first was a decrease in dopamine transporters - proteins embedded in the membranes of brain nerve cells that mop up extra dopamine - when compared with people who had died of a cocaine overdose and drug-free people who died of natural causes or trauma.
Cocaine and other narcotics, as well as extreme stress, can cause an increase in dopamine. So if someone using cocaine or under stress happens to have fewer transporters than normal their brains would end up awash with dopamine, says Mash. The extra dopamine could then cause heart malfunctions and problems regulating body temperature, leading to death. "Whether it's environmental stress or the crack pipe, it's going to trip the switch," she says.
Comment: In a state of "excited delirium", one can only imagine how tasering would assist in "tripping the switch".
How often is it that a cop is found guilty of abuse by his peers? Why new excuses when they increasingly couldn't care less what the public thinks, feels or says?