The Need for a Polygraph Investigation
How do we know that the person under investigation is telling the truth? Or how do we eliminate some suspects and narrow the pool of suspects down? These are some of the questions advocates and law enforcement ask themselves on a daily basis. Even we as human beings tend to wonder if the information we get daily is truthful or laced with a tad bit of lies and white lies. Wouldn’t it be great if we could just discern the truths from the falsehoods? Well, the world of polygraph investigation is wrought with controversies and mysteries as most people who are convicted on the basis of the polygraph tests they did say it was highly inaccurate and has an extremely high error margin. Setting aside all these issues, a polygraph is as good a device as any to help in piecing together the truth from the lies.
A polygraph is a gadget that records certain physiological changes in an individual undergoing probing in an attempt to get hold of truth or deception. A polygraph concurrently records a minimum of respiratory activity, galvanic skin resistance/conductivity and cardiovascular action. The person administering the polygraph test asks the questions, prepares the subject matter for the investigation, interprets the data, and operates the machine. The polygraph investigation usually start by simple questions like the name, date of birth, place of residence and move on to more complex questions about the matter under investigation. It the questions are usually phrased in such a manner that the person taking the test either gives an affirmative or negative response, no ambiguous answers. The physiological changes in answering the simple questions are compared to the physiological changes in answering the complex question about the matter under investigation. The examiner notes the variations and analyzes them to determine whether the examinee passes or fails the polygraph test.
The results of the polygraph investigation are used as an investigative aid. The results which are obtained are used with more in depth and standard investigative aids and techniques. Taking a polygraph test is voluntary and the data collected may help in obtaining information that can be used as evidence; may lead to a voluntary confession; and may serve as leeway for formulating hypothesis and strategies that can lead to the arrest of a suspect. The polygraph test will also assist in: Eliminating suspects, Recognising phony complaints, testing informants to determine the reliability of information provided, providing a fresh insight to an investigation when all other standard analytical techniques have been exhausted, narrowing the focus of enquiry, gathering supplementary information and proof and assisting to centre the investigation on specific suspects. This goes to show that the polygraph test may be used by many investigators in civil and criminal cases as well as vetting informants for the police as well as the private investigators.
A private investigator is considered the best placed individual to carry out a polygraph investigation because they are a neutral party to the investigation and they have the analytical skills to logically deduct useful information from the polygraph test. This is because the test is usually conducted in the absence of a confession, lack of corroborative evidence, difficulty in determining whether an individual is telling the truth or has any information relating the matter under investigation. A number of criminal and other grievous crimes remain unsolved due to the absence of substantive or confirmable leads. There are legal aspects and procedures in conducting a polygraph test and analysing the information, as well as an outlined way of presenting the evidence obtained from the polygraph test in a court of law if the evidence is to be admissible in court. A private investigator has the legal knowledge to ensure that the administering of the test is done in a legally acceptable manner as well as the legally accepted way of recording and presenting the evidence. If you need to establish the truth a certain matter, do not hesitate to visit an investigator conversant with the polygraph.