How effective is a polygraph examination?

A more common name for a polygraph test is a lie detector test. Many law enforcers have relied on it to identify perpetrators that commit heinous crimes and offences. One of the most common offences and crimes includes harm to minority communities such as LGBTQ members, African Americans, and more.

Crimes of racial abuse and homophobic assaults are usually difficult to file a case against. This is because the offenders quickly deny any claims against them to the officials. In these instances,  marginalized victims have no option but to suffice to their lack of proof against the culprit.

A polygraph test can be instrumental in such instances. Law enforcers can use this examination as an important tool that ensures that the criminals do not get away from the crimes they have committed.

How does a Polygraph Examination Work?

In simple terms, a polygraph test measures a person’s reactions in their body when they face certain questions. Many professionals use this exam for numerous reasons. You can find law enforcers of all levels seeking the help of polygraph examiners during their investigations. Similarly, this examination is also useful for private investigators and can make their job much easier.

One of the reasons someone would use this test is to clear someone of a crime if they are a suspect. On the other hand, this examination is also a good way to confirm that a particular person is a crime suspect. Often, investigators will include polygraph testing as part of their interviewing process.

It is important to note that these tests are not admissible in court, so their results will not help an individual inside the walls of a court. Instead, these tests are more of an investigative aid. The idea of a polygraph test is to tie sensing tubes to the chest and the stomach, which connect to a reader system. Males are typically belly breathers while females generally are chest breathers, so investigators make sure they cover both areas.

By doing this, investigators can look for breathing patterns that can be suspicious in the face of a problem. Typically, when a person tells a lie, they will hold their breath, or their breathing will involuntarily slow down. This impacts cardio and blood pressure, and the polygraph changes become evident.

This examination also detects any slight spikes in your blood pressure, heart rate increase and other bodily responses when a person is telling a lie. Another bodily response that private investigators often look for is a galvanic skin response. This is the electrical conductivity in the skin when it is reacting to fear. When a perpetrator tells a lie, they relive that lie in their head. The fear of being caught in the lie triggers the nervous system to emit a response.  In other words, tied to the polygraph tubes, a perpetrator will not get away with their lies. Instead, the machine will gather their uncontrollable responses.

Uses and modernization

Besides verifying claims and detecting lies, polygraph tests are handy for many other applications. Courtrooms, corporate offices, federal agencies use polygraph tests to secure jobs. They use this examination when conducting a criminal background check or running through other suspicions that they have against an employee.

The polygraph machine was invented in 1921 by a Californian Police Officer. Today, lie detectors have entered the digital age. You can now find computerized polygraphs. Modern polygraphs integrate the use of motherboards and generate plenty of data. Motherboards help these detectors process all the data, putting the perpetrator’s fate in the hands of the computer, devoid of any human error.

How effective are they?

Despite their effectiveness in most cases, no one can guarantee that every lie produces the same reaction. Poker players may have their unique tells, but there are not enough signals that work for every human since each person is different. A polygraph test tries to detect a lie by measuring stress indicators with many sensors.

Current machines record four signals, from your breathing rate to your chest and abdomen expansion. They also measure your cardiovascular signal, which is the pulse, along with the conductivity of your skin. Ultimately, it tries to measure the part of your nervous system that springs into a fight or flight response.

While feelings have a link to deception and fear of being caught, they also link to the fear of being incorrectly labelled a liar. Nonetheless, a good private investigator or polygraph examiner is aware of this and will examine by mixing controlled and relevant questions. The control questions encourage suspects to lie and make them feel nervous.

An example of a relevant question would be, “Did you beat your mother?” while the controlled would be generalized, asking whether the suspect has ever thought of beating someone. The idea behind this is that an innocent person is supposed to show more apprehension towards the controlled questions rather than the relevant ones. This is because they may worry about a recent crime that they did not commit.

Get a good Private Investigator in Oklahoma City

Finding a good polygraph examiner who knows the little nuances present in lie-detecting can be tough. Therefore, you must seek services from someone with years of experience handling tough cases.

If you are looking for a polygraph examiner OKC, we can help you. We provide private investigators that have years of expertise in polygraph testing. We have successfully used this examination to prevent racially discriminatory and homophobic incidents from ever happening again.