Lie Detection in Criminal Justice

This is FREE sample
This text is free, available online and used for guidance and inspiration. Need a 100% unique paper? Order a custom essay.
  • Any subject
  • Within the deadline
  • Without paying in advance
Get custom essay

Criminal justice can be one of the trickiest fields to get into because there are moments when a person could be lying, and no one would be the wiser. In a justice system people are able to give false testimonies and lie about events that have occurred resulting in the misappropriation of justice. Another issue with finding out the truth in certain people with regards to race, emotion, facial movements, and many more small nuances. For example, people who lie tend to try and avoid direct eye contact when they are lying, but that’s not always the case. With regards to psychology some people might be better equipped to lie to someone face and give no indication on whether or not they are lying.

There are usually two ways to tell if someone is telling the truth with regards to the justice system in the United States and that would be looking for physical changes or finding the neural changes. Physical changes someone could make while lying would be fidgeting, looking away from the questioner, stumbling over words, sweating, pupil size, or tensing of the muscles. All those are signs that someone is lying, but that isn’t always the case.

For example, there are multiple accounts where people can remain perfectly calm while lying and show no physical sign that they are struggling. However, just because they are showing no physical change doesn’t mean that they don’t know they are lying. With that said, people who lie tend to show they are by the neural impulses their brain fires away around their amygdala. The amygdala is brain structure that is responsible for processing and developing emotional reactions for a person.

Psychology and the basic understanding of how human beings function suggests that it is significantly harder to lie without having your brain activity go haywire. Therefore, neural impulses in the amygdala are the best way to determine whether or not someone is lying. However, to determine that you would need to be hooked up to a polygraph which is a basic lie detector that mostly is accurate with its readings. While polygraphs are designed to be unbeatable there are of course ways to trick a polygraph, only with the right set of training and knowledge. Tricking a polygraph is harder then tricking a person with the normal physical features one would have while lying.

While all this information is overwhelming it is quite easy to see how lying can be countered through simple physical features. For example, almost everyone has told a lie in their life where they didn’t feel bad and the other person didn’t realize they were lying. This example means that anyone can simply hide certain things from someone and thus that person can not see or understand that they are not telling the truth. Furthermore, even though its easy to trick someone physically, its significantly harder to trick someone who is conducting a polygraph because the machine measure brain activity as well as heart rate and blood pressure. With that all said, the best way to figure out if someone is telling the truth or not is by looking at their neural activity while they are being questioned.

As discussed in the first question, lie detection technology should be used in circumstances where the right answer matter such as the justice system. That doesn’t mean that lie detection technology should be used exclusively in the legal system. Therefore, it should also be implemented in job interviews or in circumstances where the right answer matters. For example, someone who is applying as a Drug Enforcement Agent should be a drug addict and a lie detector will accurately figure that out. Moreover, that doesn’t mean lie detectors are perfect because nothing is truly perfect because certain people can outsmart the lie detector.

In our society governments use special agents that are able to go other countries and collect intelligence and continue a cover, so no one knows what they are up to. For example, there have been multiple cases where a special operative from the united states is captured by government an interrogated using a lie detector. Almost every time these operatives pass with flying colors because they know how to beat the lie detectors, which means that lie detectors are not always going to be the best option when determining if someone is lying or not.

However, the average person does not have this special type of training so its normally safe to assume that they are susceptible to the use of lie detector technologies. Furthermore, these technologies are also meant to be administered by someone who can read body language so the person being tested has to be able to lie in two different ways. Therefore, lie detector technology is still one of the best ways to figure out if someone is telling the truth or not.

With all that considered, there is still one more thing that needs to be figured out when dealing with this type of technology. The issue at hand typically is what type of lie detector works best and will be the best in determining if someone is guilty or not. Traditionally there are three main methods to consider when dealing with lie detectors and that is the polygraph, electroencephalography (EEG), and a functional magnetic resonance image (fMRI).

Since those are just a lot of big words lets define what each of the test measure and demonstrate. A polygraph is a test that measure the heartrate and breathing of a person but is solely dependent on whether or not the person administering the test can see any deceptions. An EEG is a graph that detects electricity in the brain and can be isolated to see if certain areas are lighting up more than others. Lastly, an fMRI is a test that measure brain activity through the use of the blood in the brain, basically the brains blood flow and electricity show what’s going on.

While there are a lot of flaws with the traditional polygraph its still one of the most popular and quickest ways to determine if someone is lying. Since the test relies heavily on whether or not the administer can determine if the person is making any body changes that suggest deception, its safe to assume they need to be extremely qualified. Therefore, polygraphs are one of the quickest and least expensive lie detectors because it doesn’t do any brain scans and the average Joe is not going to be able to trick the polygraph.

Furthermore, a polygraph can be set up in an office or a room and doesn’t require a brain scan once again being the cheaper alternative to the lie detector discussion. With that said, the best part about a polygraph is that they have a specialist that is trained in reading and understanding body language, which means if something gets past the machine the administer will see it or vice versa. All in all, the polygraph is the cheapest and most convenient way of determining if someone is lying or not.


  1. Grison, S., Gazzaniga, M, S. (2017). Psychology in Your Life. New York, NY: W. W. Norton & Company.

Cite this paper

Lie Detection in Criminal Justice. (2021, Jun 28). Retrieved from https://samploon.com/lie-detection-in-criminal-justice/

We use cookies to give you the best experience possible. By continuing we’ll assume you’re on board with our cookie policy

Peter is on the line!

Don't settle for a cookie-cutter essay. Receive a tailored piece that meets your specific needs and requirements.

Check it out