By Topher Sanders and Ryan Gabrielson, ProPublica
Over the first several months of 2014, the Hillsborough County Sheriff's Office arrested 15 people on drug charges only to have the Florida state crime lab determine the substances thought to have been drugs in fact were not.
The arrests had been made by deputies on Florida's Gulf Coast using what are known as chemical field tests — inexpensive kits designed to detect the presence of illegal drugs. A suspected substance is dropped into a pouch of chemicals. The liquid turns a certain color if the substance is, say, methamphetamine or cocaine.
Amid the rash of mistakes, Christopher Baumann, a lieutenant who'd worked narcotics and homicide at the agency, decided to conduct an experiment. He placed material listed as methamphetamine into a kit specifically meant to indicate methamphetamine and watched as the liquid in the pouch turned a purple-ish color. He understood that to mean the test was positive for methamphetamine. Then he activated another kit — cracking open ampules of the chemical reagent — but placed nothing inside the pouch. The liquid turned the same color.
Baumann, concerned, notified his superiors of his results in a memo. They took swift action: Officers in the department were ordered to turn in their remaining field test kits. Prosecutors dropped charges against a number of people arrested for possession of methamphetamine, according to the local public defender's office.
But sheriff's officials subsequently made an embarrassing discovery. It was Baumann who had erred, not the tests. He'd misinterpreted the color changes. The department had to notify the local prosecutor again, though little could be done about the methamphetamine arrests that might have been dismissed prematurely.
Beyond scuttling a handful of cases, Hillsborough County's confusion reflects a broader issue with field tests, which are used by thousands of law enforcement agencies across the country to bring drug charges and obtain guilty pleas from those charged.
Many officers appear to receive little or no formal training in the proper use and interpretation of these tests and there are no requirements for them to do so.