Common drug tests lead to tens of thousands wrongful arrests a year

Original Article ↗ Hacker News Discussion ↗

Inexpensive roadside drug tests used by U.S. police are alleged to produce high false positive rates, leading to tens of thousands of wrongful arrests and coercive plea deals, especially for poor defendants who cannot afford to wait in jail for lab confirmation. Commenters argue that if accurate laboratory testing is too slow or costly, those drug offenses should not be prosecuted at all, and that arrests should never be based solely on screening tools explicitly labeled as non-confirmatory. The exchange broadens into criticism of the war on drugs, bail and plea-bargain incentives, and a justice system whose practical outcomes—rather than stated goals—disproportionately punish vulnerable people.

Field Drug Test Accuracy and Misuse

  • Colorimetric field tests are described as cheap, fast, and widely used despite high error rates.
  • Cited figures: ~4% false positives in lab conditions, 15–18% in the field, and one NYC jail-mail program where 91% of positives were later found false.
  • Tests are labeled by manufacturers as screening-only with mandatory lab confirmation, yet are reportedly used as de facto proof for arrest and charging.
  • Some note these tests are also unreliable for safety/harm-reduction: ambiguous colors, test aging, and non-uniform samples.

Plea Deals, Bail, and Coerced Outcomes

  • Many arrested on the basis of field tests reportedly take plea deals because they cannot afford months in jail while waiting for lab results.
  • “Trial tax” is criticized: sentences after trial can be dramatically higher than plea offers, pushing even innocent people to plead.
  • Public defenders are portrayed as overworked, underpaid, and incentivized to negotiate quick pleas, especially when a test appears “failed.”
  • Bail is framed as a “pay-to-win” system that bakes inequality into outcomes and enables coercive pleas.

Rights, Speedy Trials, and Waivability

  • Debate over what would happen if speedy-trial rights couldn’t be waived and plea deals were banned: some predict mass dismissals and more rational charging; others fear system overload and vigilante justice.
  • Example from NYC where requiring prosecutors to have all evidence ready by the speedy-trial date reportedly drove many low-level dismissals.
  • Broader philosophical argument on whether any rights (e.g., speedy trial vs. anti-slavery) should be waivable and what “waiver” really means.

Drug Policy and Testing Philosophy

  • Some argue that if tests can’t show current impairment (e.g., THC metabolite tests) they shouldn’t be used for DWI or similar offenses.
  • Strong support for legalizing and regulating drugs (and sometimes prostitution), treating them like alcohol/tobacco, emphasizing harm reduction, quality control, and taxation.
  • View that responsible, educated drug use is common but invisible; current “war on drugs” is seen as a failure that will be judged harshly by history.

System Incentives and “Purpose of the System”

  • Several comments stress that systemic outcomes (wrongful arrests, criminalization of poverty) reveal the system’s true “purpose,” regardless of stated intent.
  • Others counter that this maxim overstates intent and can become a shallow rhetorical attack; they distinguish between designers’ intentions and emergent purposes.
  • Discussion of prosecutors, private prisons, and police funding being tied to arrests/convictions, creating perverse incentives.
  • Dispute over politically backed district attorneys: some see them as corrupt subverters of law; others as democratically elected actors correctly using discretion against unjust laws.

Policing Priorities and Selective Enforcement

  • Repeated anecdotes of police ignoring property crimes (bike thefts, burglaries, stolen phones) unless large retailers provide gift-wrapped evidence.
  • Perception that police prioritize protecting property of “nobles” (wealthy individuals, corporations) over everyday victims, in the US and in some European countries.
  • Discussion of legal authority for shopkeepers to detain suspected thieves and the practical risks they face if wrong.

Proposed Reforms and Alternatives

  • Suggestions to:
    • Forbid arrests based solely on field-test results and require lab confirmation before charging.
    • If tests are kept, penalize officers proportionally when a field-test-based arrest proves false, to align incentives.
    • Reduce or abolish bail, given its role in coercing pleas.
    • Eliminate or tightly regulate plea bargains; require equal sentencing whether via plea or trial.
    • Limit prosecutions when proper scientific testing is too costly/slow—if you can’t test accurately, don’t criminalize.
    • Hold state labs accountable for refusing or delaying confirmatory testing.
    • Sue or regulate test manufacturers more aggressively if they oversell accuracy.