Can the Police Use a Polygraph in My Criminal Case?
Imagine being walked into a very small room where the police put you in a chair and start wrapping wires around you and attach things to your arm and hand and then start interrogating you like you have never seen in your life until you “tell the truth.” Think it doesn’t happen? It does, and it does right here in Minnesota. If you are facing serious criminal charges in Minnesota and the police tricked you or trying to trick you into taking a polygraph or “lie detector”, make sure you consult with an experienced Minnesota criminal defense attorney. Even more, make sure that lawyer is also a Board Certified Criminal Law Specialist. If the criminal defense attorney has also been on the receiving end of a polygraph multiple times, even better.
“The police sometimes like to call a polygraph a Lie Detector. It isn’t. The police will lie to you about that too.”
What is a Polygraph and How Does it Work?
A polygraph is a machine that measures and records multiple physiological responses that are supposedly designed to determine a person’s emotional state, not truth or falsehood.. The physiological responses include:
Blood pressure and heart rate;
Repiratory or breathing rate;
Skin conductance (sweating);
Muscle activity during the interrrogation.
“The problem is that the polygraph is based upon junk science. They don’t determine truth versus lie. They never have. In fact, polygraphs are simply not admissible in Court here in Minnesota.”
So, the Polygrapher will wrap a blood pressure cuff around your arm that is called a Cardiosphygmograph, a flexible tube called a Pneumograph around your chest and also small electrodes attached to your index and ring fingers called a Galvanograph. These all sound very scientific but they aren’t. All of these devices will have wires attached that feed the information to the polygraph device. The machine will then produce a set of squiggly lines that allegedly show changes in breathing, sweating, movement and blood pressure and heart rate. The logic is that if you are lying, these numbers will change and if you are telling the truth, they won’t. Here is the thing, the machine doesn’t say that you are lying. Seriously. It just shows changes but nothing proves that those changes mean deception, that you are lying.
The purpose of a polygraph is to get as much information as possible. and the polygrapher uses this device as a tool to get that information. They will start by asking a series of baseline questions and then start pushing. They will regularly mention deception and then use it to push further and further. The problem is that the polygraph is based upon junk science. It was never able to tell the difference between a truth and a lie. In fact, polygraphs are simply not admissible in Court here in Minnesota.
“The logic is that if you are lying, the machines graph will change and if you are telling the truth, they won’t. Here is the thing, the machine doesn’t say that you are lying and never has.”
Because the police frequently threaten with a polygraph, this really is about coercion and intimidation. The police are looking for a confession or admissions that fit their theory of the case. They already decided you did it, whether you did or not. They just want more proof. It is important to realize that this may result in a successful suppression of statements.
If this sounds like I have strong opinions regarding the polygraph, its because I myself have faced such a device many times as a former CIA Officer. The problem is, the polygrapher is not a doctor and really nothing but a trained interrogator who uses the machine as leverage. As a result, if you have faced such a device and are facing charges, make sure you sit down with an experienced Minnesota criminal defense attorney. It matters.
Go with the Best
Jack Rice is a nationally known and respected criminal defense attorney who is located in St. Paul, Minnesota. Jack is also a former prosecutor and former CIA Officer. Contact Jack Rice Defense for a free confidential consultation or call 651-447-7650 or 612-227-1339. Jacks got your back.