The debate has centred on whether the results of polygraph tests should be admissible as evidence in criminal trials. The inherent uncertainties surrounding polygraphy have led judges to exclude them over questions of scientific validity. But prosecutors continue to push for their acceptance, resulting in recurrent courtroom fights.
While the Frye ruling prohibited polygraphs in federal cases, state courts could set their standards. Some states like New Mexico chose to allow polygraph results under certain limited conditions. They were, however, mostly excluded in adherence to the Frye precedent. It was not until the 1960s and 70s that efforts to admit polygraph tests accelerated, led by prosecutors seeking to validate the device. They argued advances had satisfied scientific standards. The situation prompted renewed legal clashes.
1983 congressional ban
The widespread push to permit polygraphs lie detector test florida alarmed Congressional leaders who cited flawed science. They passed a law in 1983 flatly prohibiting both federal and state courts from using polygraph evidence in trials. For a decade, this congressional ban settled the debate and uniformly blocked polygraphs from courtrooms nationwide. However, controversy later resurfaced after the 1988 Employee Polygraph Protection Act excluded criminal suspects from the ban.
In the 1993 case Daubert v Merrell Dow Pharmaceuticals, the Supreme Court overturned the Frye precedent on scientific evidence. It established a new flexible standard asking judges to assess: testing methods, peer review, error rates, standards, and general acceptance. This provided another opening to argue polygraphs met admissibility requirements. Proponents invoked Daubert in asking courts to reevaluate polygraph bans.
Renewed state admissibility
Citing Daubert, some state courts did overturn categorical exclusions, though most imposed restrictions when permitting polygraphs. New Mexico led the way in allowing results under its rules of evidence. Other states like Arizona and Missouri also permitted polygraphs conditionally, typically if both parties consented. But many states retained bans given inconclusive science. Admissibility remained limited and variable nationwide. The federal ban also stood.
Debates over courtroom polygraph use continue in state legislatures and judicial proceedings. Arguments call polygraph techniques unreliable “junk science” that juries overvalue. However, proponents invoke improvements in test methods and the need for all available evidence. Courts are also divided. In 2016 the Massachusetts Supreme Court affirmed blanket inadmissibility, but an Ohio court recently permitted a polygraph.
Several factors still drive exclusion. Polygraph validity depends heavily on examiner competence and trial conditions differ from controlled settings. Tampering techniques also enable subjects to manipulate results. And adverse judges warn that allowing polygraphs would overwhelm trials with time-consuming disputes between expert witnesses. Evidentiary bans stem from these lingering scientific doubts and pragmatic trial concerns.
The courtroom status of the polygraph remains unsettled as a highly variable patchwork. Tensions endure between prosecutors arguing for greater use and skeptics deeming methods insufficiently reliable for legal evidence. As technology evolves, the debates may be reactivated in legislatures and courtrooms. But for now, polygraphs face ongoing hurdles to admissibility in many jurisdictions due to conflicting expert opinions on their scientific standing. The trials go on.