Why You Should Never Talk to the Police

To protect and to serve. That has been the motto of the Los Angeles Police Department since 1963. Since then, it has been adopted by many other police forces around the United States. Similar mottos have been adopted around the world. So why not help the people who are here to protect and to serve us by talking to them? Behavioral science gives us insight into the dangers that lurk in the dark when people sit down to talk with police officers.


– How to use the insights from behavioral science to improve your health and wellbeing –

Reading time: 11 minutes

Imagine you are asked by detectives to come to the police station. They want to talk to you about a crime that occurred the week before. Say a stabbing incident where someone got seriously injured. Obviously, you want to help find the perpetrator who is still on the loose. Why the police wants to talk to you, you have no idea. Since you have nothing to hide and are a righteous citizen that is willing to help, you do as you are asked.

The interview

Two detectives warmly welcome you at the station and show their appreciation that you have made the effort to come and talk to them. The interview starts off with some pleasantries and questions about your background. Slowly but surely though, the questions loose their lightness. You start to feel a little uncomfortable. The detectives want to know where you were Thursday night at the time of the stabbing. “At home“, you tell them truthfully. “Anyone that can corroborate your story?” they ask. Since you were home alone watching a soccer game on TV, there is nobody who can give you an alibi that would prove you were at home and nowhere near the incident. By now you start to get really nervous. Do they actually think you committed this crime?

Before you can even clear your thoughts, they drop a bombshell. Not only do the detectives have an eyewitness that has identified you as the perpetrator in the stabbing incident, they also found your DNA on the knife that was used and left behind at the crime scene. You vehemently deny to have anything to do with the crime. But you also start to think that you may have misremembered that you were at home on Thursday night. Maybe you only saw the highlights of the soccer game the next day. You agree with detectives that you must have been at the crime scene around the time of the incident. After all, both an eyewitness and your DNA prove that you were. But only to visit a friend who lives close by, you tell the detectives. Then you ask for a lawyer. This is when the interview ends. But by now, the damage has already been done.

Good guys or bad guys

Police officers are by and large the good guys. Most of them are professionals who keep our streets safe. But their training in behavioral science is limited. And above all, they are still human. That means they are flawed and sensitive to unconscious bias like the rest of us. In the imaginary scene above, where you were depicted as a suspect of a stabbing incident, there are already multiple biases at play. And they can get you locked up for a crime you didn’t commit.

1. Guilty behavior

When the questions the detectives asked made you nervous, you showed guilt in their eyes. Why start to sweat, become fidgety with your hands and search for the right words, when you have nothing to hide? The detectives are now even more convinced they got the right person.

But what if you kept it cool, because you have a stable character that isn’t easily brought off balance? Or maybe you were nervous, but didn’t show it. The logical conclusion would be that if nervousness shows guilt, than coolness shows innocence. However, this is not how the human mind works. You were already a suspect in the eyes of the detectives. That is why you were brought in for questioning in the first place. The detectives are now looking for confirmation of their suspicion. If you played it cool, you also confirmed that suspicion. Because keeping it cool in an interview with detectives about a serious crime, only shows them the callousness that it takes to stab someone.

So no matter what your behavior was, you showed guilt in the eyes of the detectives. This is called confirmation bias. It is the tendency to search for, interpret, favor, and recall information in a way that confirms or supports one’s prior beliefs. It may not be admissible as evidence in a court of law, but you have just made yourself their prime suspect. Just by talking to the police. And that can have serious consequences.

2. Eyewitness

The detectives told you in the interview that there was an eyewitness to the stabbing incident. The witness has positively identified you as the perpetrator. What the detectives didn’t tell you is that there were four other witnesses and that none of them recognized or identified you as the stabber. And they certainly didn’t tell you how memories can be distorted.

Most people think that memory works like a video recording that can be retrieved at all times. In reality, memory more often resembles a Wikipedia page where things are constantly changing. Professor Elizabeth Loftus explains in her book ‘Witness for the Defense‘ how memories can be influenced by wording alone.

When participants in an experiment were shown footage of a car accident, they were separated into two groups. The first group was asked how fast the car was going when it hit the other car. The second group was asked how fast the car was going when it smashed the other car. The group that got the smashed instead of the hit version of the question, reported a significantly higher speed of the car during the incident (41 mph versus 34 mph). The group that got the smashed instead of the hit version of the question also reported to have seen broken glass after the incident significantly more often (32% versus 14%). The most interesting thing about the latter finding was that there wasn’t any broken glass to be seen at all. It was a false memory stimulated by the wording of the question.

It has also been established that memories are reconstructed by media information, by talking to other people or simply conflation. Maybe the eyewitness saw you running a couple of days after the incident when doing your weekly 10K. If the perpetrator ran away after the stabbing in a similar stride and outfit, the memories could conflate. Dr. Julia Shaw calls this the memory illusion in her book by the same name. And it is not an anomality. Mistaken eyewitness identifications contributed to approximately 69% of the 375 wrongful convictions in the United States overturned by post-conviction DNA evidence according to the Innocence Project. In some of these cases, the wrongfully convicted were on death row waiting for execution. So a witness statement isn’t as solid as people might think. But what about your DNA that was found on the knife?

3. DNA

Evidence involving DNA is considered more robust than an eyewitness statement. And it should be. During the stressful interview with the detectives you never asked how the police got a match with your DNA and the DNA found on the knife. You never gave them your DNA before or during the interview. And since you have a clean sheet, your DNA isn’t in their DNA database either. So how could they have a match? Well, they didn’t. They lied.

What most people don’t know is that American detectives are permitted to lie about evidence to suspects to get information or a confession. Although shocking, you may also consider this great news. Now the detectives can actually run a real DNA analysis and the result will come back negative. That means the misunderstanding is resolved and all ends well for you. Although this sounds more than reasonable, you can’t count on it.

During the interview you stated that you might have been visiting a friend on Thursday night. So the detectives not only have an eyewitness who identified you as the perpetrator, they also have your statement that put you at the scene of the crime during the incident. And things can easily get worse. When the police searches your house, they find a dark colored hoodie that matches the description by the eyewitnesses of what the perpetrator was wearing. But who doesn’t own a dark colored hoodie? And besides, the clothing is one of the reasons why one of the witnesses misidentified you in the first place.

When the real DNA results come back, something really amazing happens. The result comes back negative. It wasn’t your DNA on the knife. Just as you told the detectives all along. But instead of dismissing you as their suspect, the detectives dismiss the negative DNA result. In the 1989 rape of a 28-year old woman that went jogging in New York’s Central Park, the police soon apprehended five teenagers. When neither of their DNA matched the semen samples found on the victim, the police simply dismissed the results. The Central Park Five, as the teenagers were later labeled, were all convicted with the theory that just because the police didn’t get all of them, it didn’t mean they didn’t get some of them.

The Central Park Five collectively spent 41 years in prison until Mathias Reyes admitted raping the female jogger. His DNA did match with the semen samples found. The dismissal of the negative DNA results with the narrative that one of the attackers got away can be explained with the theory of cognitive dissonance. This theory describes the mental discomfort that results from holding two conflicting beliefs, values or attitudes. Because people seek consistency, people want to resolve this tension. In the case of the Central Park Five, there was tension between the belief that the five teenagers were guilty and the non-matching DNA results. An easy way for detectives to reduce tension was to dismiss the negative DNA results. It allowed them to hold on to their belief that the five teenagers were guilty.

So when the DNA result comes back negative in your case, don’t be surprised if the detectives come up with alternative explanations for the mismatch. They might suggest there were two perpetrators. Or that an unknown and innocent bystander picked up the knife before the police confiscated it. The Dutch police came up with an even more bizarre theory to reduce cognitive dissonance when the DNA results didn’t match their two suspects in the rape and murder of flight attendant Christel Ambrosius in 1994. They theorized that the semen sample found on the victim’s leg was the result of a voluntary sexual contact before the rape. The detectives reasoned that because of the rape, the semen from the voluntary sexual contact was dragged out onto the victim’s leg. That is how the non-matching DNA semen sample landed on the victim’s leg. If this theory sounds more plausible than the theory that you simply got the wrong suspects, cognitive dissonance is at play. Despite the mismatch, suspects Wilco Viets and Herman du Bois were both convicted of the rape and murder and spend seven years in jail. It wasn’t until 2008 that the real perpetrator, Ronald P. was found through newly administered DNA to the national database and convicted of the crime.

The Central Park Five and Dutch suspects Wilco Viets and Herman du Bois were convicted on the presented evidence in their cases. Not in the least because of their own confessions. Confessions made by the suspects under intense pressure during interrogation. All confessions turned out to be false. They were all revoked shortly after the interrogations stopped and long before the trials began. The police should have focused their attention elsewhere when the confessions were revoked and the DNA didn’t match the suspects. But they didn’t. And innocent people spend years incarcerated for terrible crimes they didn’t commit. The detectives in both cases got tricked by their own unconscious biases. So what should you do when the police wants to talk to you?

What you gonna do when they come for you?

When the police wants to talk to you about the stabbing incident discussed earlier, you tell them you are more than willing to help. Then you give the detectives the contact details of your lawyer. If you don’t have one, ask for one. If you are not entitled to an lawyer yet, don’t talk to them until you are. By lawyering up immediately, you probably show guilty behavior in the eyes of the detectives. Why else would you immediately ask for a lawyer if you have nothing to hide?

But even if you do talk to them directly, the detectives will probably find a reason to confirm their suspicion as we saw earlier. By speaking with the police through a lawyer, you will protect yourself from the detectives’ biases getting you in trouble. Your lawyer will correctly value the eyewitness that positively identified you as useless, as it turned out to be an 82-year old woman who saw the perpetrator from 200 feet away in almost complete darkness at 10:30 PM. Your lawyer will also find out about the four other witnesses that didn’t recognize or identify you as the stabber while they were standing much closer to the incident than the 82-year old woman. Your lawyer will probably laugh out loud when the detectives claim to have a DNA match without even having a sample of your DNA. And lastly, your lawyer will make sure you don’t implicate yourself be stating that you were at the scene of the crime when you were not.

If the police wants to talk to you, you better call Saul or any other lawyer to protect you from detectives’ biases.

If you want to help the police solve a crime, you can obviously provide information to help keep your community safe. Just make sure you do it through a lawyer. Either it be Breaking Bad’s Saul Goodman or someone a little more trustworthy. Otherwise, the results can be devastating. Because from what I have heard, the prison food isn’t very healthy and being locked up in a small confinement isn’t particularly good for your wellbeing either.

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About the author

Sander Palm (1980) is a behavioral economist and fitness enthusiast. He has a Master of Science in Marketing from VU University Amsterdam. He lives and works (out) in The Hague. Want to know how you can get your marketing, communication and sales in better shape? Drop an email at sander@behavioralinsight.nl

Source of top image: Nick Page on Unsplash



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