DNA evidence has revolutionized the area of criminal law justice. In many cases, DNA evidence can be used to link specific people to crimes, but it can also be used to exonerate those who have already been convicted.
These exonerations paint a very clear picture, showing that eyewitnesses are wrong consistently, and that they often give testimonies that are inaccurate and that contribute to these false convictions. DNA can clear some of these convictions after the fact, but not all of them. Why is it that witnesses are wrong?
Memories can change
For one thing, your memories do change over time. This has been shown to happen with recall. That suggests that simply thinking about what happened or discussing it with someone else could make you remember it differently. A witness may think that they accurately remember exactly what happened, and so they will take the stand and sound exceedingly confident, but they’re really giving an account that they’ve created themselves, not a rendering of what happened.
Witnesses may be biased
There’s a reason that it’s best for a jury not to engage with the news regarding a case that they’re involved in, but witnesses can also be influenced by outside factors. They may see the way that the news is being spun and then accidentally alter their account to fit this. They could also be biased based on things like the age, race or gender of the alleged perpetrator. They may not even understand that they hold these biases, but they can make them more skeptical of these individuals and may make them testify against them.
Most witnesses didn’t plan to witness anything
Finally, the standard eyewitness is not somebody who ever thought they were going to see criminal activity. This means that they are often unprepared for it, they don’t have good sightlines, they feel like things are happening quickly and they may be nervous for their own safety. All of that means that their memories can be tainted or that they may miss key details.
If you are going to court and there is a witness testifying against you, it’s important to know that this person may be wrong and to understand your legal options.