Being stoned does not necessarily make you a bad eyewitness

Being stoned does not necessarily make you a bad eyewitness

Being stoned does not necessarily make you a bad eyewitness.

A recent study by Vredeveldt et al has shown that witnesses to a crime could pick the thief out of a line up just as well if they had been smoking marijuana as if they had not.

Participants were asked, either before or after consuming marijuana in a coffee shop in Amsterdam, to watch a video of a robbery. Then, after a short interval, they had to describe what they had seen, and try to say whether the robber was in present in a police lineup.

The more stoned participants were not so good at giving details of the crime generally, which might make them less well believed by judges and juries. However, they were as good as sober participants at identifying whether the thief was in the lineup or not. Curiously, the intoxicated ones were more likely to be correct if they were confident than the sober ones were if they were confident.

This is only one study, and it is not perfect. For example, the people were presumably all consumers of marijuana generally as they were going into a coffee shop which expressly offers this service. Some of the participants who were deemed sober because they were going in may therefore already have partaken somewhere else; or there may be an overall long term effect of the marijuana which would have affected all participants.

And the list of possible flaws goes on. However, from this study, it appears that being high on dope doesn’t necessarily affect your natural recognition abilities. As cannabis is made legal in more and more places around the world, it is important that studies are undertaken to discover the effects and implications this will have on society.

Find out more about how the mind plays tricks on you and how your memory works by reading my books, Bias Beware and Memory Matters.

Are Christiano Ronaldo and Brett Cavanaugh both Sex Criminals?

Are Christiano Ronaldo and Brett Cavanaugh both Sex Criminals?

Are Brett Cavanaugh and Christiano Ronaldo both guilty of sexual assault?

As I write this there are two high profile charges of sexual assault in the news. But can we believe them?

In questioning their guilt, some may say I am disrespecting their accusers, who have apparently been through a horrific ordeal. And some may say I am helping mud to stick just by writing about it. I mean no disrespect and I hope that I do not help any mud to stick to an innocent person.

Clearly, I have no idea if the two men in question are guilty or not. The reason I am writing this is that my research has shown me just how unreliable our memories are. Just because a person believes someone assaulted them ten, or twenty, or thirty years ago, does not mean it happened the way they remember it.

Study after study has shown that details are extremely easy to implant into someone’s memory of an event. And once that detail has been put in, the person can remember it no other way. A simple example is asking people if a car stopped before or after the tree in a video they watched. There was no tree, but many people, upon being asked that question, would unwittingly implant one into their memories. They cannot then remove the tree if someone just tells them it wasn’t there. They now see it in their memory as clearly as any genuine detail.

We are unable to remember how we used to recall something, as opposed to how we recall it now. So implanted details become as real as genuine ones.

I can imagine a situation where someone (like Ronaldo’s accuser) is raped. They go to the police, but cannot give firm enough details for the police to proceed with any real investigation. Years later someone suggests to this poor lady that the rapist may have been Ronaldo. She is shown pictures of Ronaldo and encouraged to “remember” that it was indeed him. The more she is encouraged and coached, the more clearly she remembers each detail. Indeed, her memory may change dramatically, with time (and perhaps the input of others), without her being aware that it has changed at all.

Many people end up believing they were sexually assaulted as children when they were not, because of terribly misinformed and damaging “therapy”. It is known that if someone is asked to imagine what it would have been like if they had experienced something (let’s say a balloon ride), they are far more likely to misremember actually experiencing that thing even though it never happened. And each time they “recall” it they recall more detail more clearly. Eventually, if they are encouraged to remember the incident, the false memory becomes as clear, if not clearer, than any other memory.

It is overwhelmingly evident that the mind can create false memories, and that real memories can and do become distorted. As further proof of this, the majority of wrong convictions in court are a result of mistaken eyewitness testimony.

One would think that the longer ago an incident happened, the more chance there is for distortion of that memory. So should we believe the accusers of Brett Cavanaugh and Christiano Ronaldo?

I can believe that the accusers are sincere, and are not lying. But I would suggest that that is very different from actually believing their memories are accurate.

Find out more about how the mind plays tricks on you and how your memory works by reading my books, Bias Beware and Memory Matters.

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