Law enforcement loves cheap drug tests. First, they're cheap, around $2/per. Second, they can turn a whole host of legal substances into probable cause for searches and arrests. Field drugs tests have converted everything from a deceased child's ashes to bird poop (on a car hood, no less) into illicit substances justifying the removal of innocent peoples' rights.

Also on the list of "illegal" substances deemed illegal by faulty field tests: donut crumbs, cotton candy, honey, aspirin, and diesel. People's freedoms were lost and their lives ruined by tests even the manufacturers know will produce false positives when testing perfectly legal substances plenty of people routinely have in their possession.

This is from ProPublica's latest report on field drug tests (a follow-up to its 2016 series on faulty drug tests), which shows the companies making drug tests know they're regularly capable of misidentifying substances.

During the Imperial County hearing, an executive at the Safariland Group, the nation's largest field test manufacturer, testified the company keeps a list of more than 50 legal substances that cause positive results. Court records show chocolate sometimes turns the liquid a similar shade of green as heroin in the NIK kits.

Safariland Group did not respond to a request for comment.

If these drug test producers are ethical, they're passing on this information to the law enforcement agencies purchasing their tests. If officers are ethical, they're well aware that a number of common substances will trigger false positives. Somewhere along the line, the ethics are abandoned. Most likely, this is happening in the so-called "field," where the drug tests are asked to do little more than give an officer permission to search a vehicle, maybe seize a little cash, and add another drug bust gold star to their permanent record. I'm pretty sure we can all guess the point where ethics are abandoned.

The Imperial County hearing referenced above is covered more thoroughly in this report. It involves a court declaring that these drug tests are too inaccurate to be allowed to negatively affect citizens' rights and freedoms. That hearing was performed in 2017 by a Judge Christopher Plourd at the California county's courthouse. Defense attorneys presented plenty of evidence showing the drug tests routinely declared legal substances illegal, only to be reversed by actual — and far more accurate — lab testing of the seized substances.

In what is likely the first time a court has dared to tell cops they can't use one of their favorite tools, Judge Plourd sidelined the NIK-brand field tests.

Plourd ruled in early 2018 that the test kit "does not meet a scientific admissibility standard" and therefore "does not support the grand jury indictment."

This sort of judicial declaration remains an anomaly, unfortunately. But the tide might finally be turning, thanks to class action suits filed by victims of the faulty drug tests. The Massachusetts Department of Corrections is the defendant currently being sued by inmates whose incoming snail mail supposedly tested positive for drugs. Violations of DoC policy meant these apparently innocent inmates were placed in solitary confinement or stripped of privileges. The field tests used to test mail were wrong more than one-third of the time.

Court records show that between August 2019 and August 2020, lab analysis found that 38% of the inmate mail that tested positive did not contain the alleged drug.

That failure rate prompted the most recent pushback against cheap tests masquerading as probable cause. The judge overseeing this case (again, a county-level judge) ordered the state Corrections Department to immediately cease use of the kits to test inmates' incoming mail.

And this recent pushback isn't just limited to a single court in a single county. It has federal implications as well, as the list of defendants also includes the manufacturers of the tests.

In September, a federal judge ruled that field test sellers can potentially be held liable for harm caused by erroneous results.

And here's another bit of good news. Prosecutors and the state/county agencies overseeing them are finally starting to recognize there's a problem here.

Courts have overturned 131 drug convictions in the past 10 years after laboratory analysis determined the alleged drugs were legal substances, according to a database maintained by the National Registry of Exonerations. A large majority of those wrongful convictions originated in Harris County, Texas, where the crime lab analyzed its backlog of suspected drugs from closed cases and discovered the evidence in hundreds of convictions did not contain drugs. 

That may be too little too late for too many people (ProPublica says most of those convicted offered guilty pleas during preliminary hearings), but it's better than the nothing being done pretty much everywhere else in the country. There's enough evidence out there calling into question field drug test accuracy that more law enforcement labs should be voluntarily testing seized substances to at least get a ballpark figure on the validity of the chemical kits they use.

But most of that evidence — which could be used to determine someone's innocence — has likely long since been destroyed. Once a plea is entered, the evidence is no longer needed to prove the case. With only a finite amount of storage and very few challenges to evidence, substances seized during normal possession arrests tend to be the first thing to go during evidence room housecleaning. In the end, innocent lives get destroyed and law enforcement agencies get to tally up more unearned wins. Hopefully, what's covered here depicts a new leading edge, rather than just the exceptions that make the rule even easier to prove.