Nothing but the truthNepal Police should not compel suspects to undergo polygraph tests, given their potential for rights violation
The Nepali accusatorial criminal prosecution system, akin to the Western criminal justice system, has failed in this quest for the truth. In between so many lies spoken during interrogation and testimony, it is a daunting task for investigation agencies to produce the truth before the judge.
Actors in the criminal justice system have tried to engage with scientists, psychologists and forensic science researchers to ascertain the truth with the help of lie detector machines and tests. The brain-based lie detection test, commonly called the polygraph, was invented in the United States and was first offered as evidence by public prosecutors in 1923 in US Supreme Court case Fyre v the United States. The court then refused to accept the results of the deception test as it held the view that such brain-based lie detectors had not yet received acceptance within the physiological and psychological authorities of that time. Since then, brain-based lie detection technologies have improved significantly but American federal courts remain hesitant to fully endorse it.
The Nepal Police routinely conducts interrogation of suspects and the accused to extract the truth. Sometimes confessions are obtained using ‘third degree’ interrogational methods, which can entail merciless beatings, deprivation of water and food, questioning in dark rooms etc. Confessions or truth extracted using such methods are a severe violation of human rights so the Nepal Police has been looking for alternatives to third degree techniques to complete their investigation and extract confessions. Hence, it gladly accepted 12 lie-detector equipments provided by the US government. Some of its officials even received training from the Academy of Polygraph Science in Fort Meyers, Florida and the Stoelting Company on using these polygraph machines. According to the US Embassy website, these polygraph machines record changes in physiological characteristics, such as respiration, heartbeat and blood pressure and are an investigative tool that police departments can use to confirm or eliminate suspects.
Violations of rights
Arguably, polygraph can be a less coercive alternative for the Nepal Police to extract information, in comparison to methods that are intimidatory, overbearing and those that can cause severe physical injury or mental strain. At times, the suspect or the accused can use such devices as mitigating evidence to prove their innocence by ‘successfully passing’ the lie-detection examination. Additionally, by resorting to polygraph examinations, investigating agencies can also make subsequent discoveries and trace more evidence, which can ultimately result in credible fact-finding. Thus, polygraph may have practical advantages over conventional interrogation methods but the larger and more important question is whether it infringes upon a person’s fundamental rights as guaranteed by the constitution.
The Interim Constitution of Nepal recognises a fundamental right against self-incrimination. The relevant provision states, “No person accused of any offence shall be compelled to be a witness against himself/herself.” In other words, during investigation, evidentiary or trial stage, the accused cannot be forced to implicate themselves in a crime.
Asserting this to be a fundamental human right, the Indian Supreme Court, in a recent case of Selvi v State of Karnataka (2010), declared that the involuntary administration of the polygraph test can amount to forcing an accused to testify against themselves. The court further added that compelling an accused to undergo a polygraph examination is a violation of the rights to life and privacy. Even in the US—the land where the polygraph was invented—the consistent view of the Supreme Court has been that polygraph tests are unreliable. In United States v Scheffer (1998), the US Supreme Court reiterated the poor reliability of the polygraph test.
Refrain from use
Thus, across major jurisdictions, evidence obtained through polygraph tests are discredited on two grounds. The first is legal—the courts have held that it violates constitutionally guaranteed rights. The second is scientific—such tests have not received the support of the scientific community.
Given the unreliability of polygraphs for forensic and legal purposes and the constitutional questions it can raise, the Nepal Police should avoid compelling suspects or the accused to undergo polygraph examinations. Until the polygraph can muster the requisite scientific credibility, it must only be used if an accused actively volunteers for it and the purpose should be limited to fact-finding, not for seeking the truth.
Dahal is an advocate