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Bite mark analysis: The junk science some courts still accept

On Behalf of | Jun 7, 2022 | Criminal Defense

You have probably heard that bite marks match people’s teeth. If they bite someone, then those bites should be able to be lined up with their dental records.

Interestingly, this is what some would call “junk science.” While it was thought of as a helpful tool in the past, bite mark analysis isn’t necessarily good evidence anymore.

How bite mark analysis works as evidence

Bite mark analysis is based on a simple foundation: Human mouths are all unique, and dental records can be used to identify if someone bit someone else. It assumes that human skin records the uniqueness of people’s mouths easily and accurately, as well.

There are many assumptions going on with bite mark analysis beyond just the idea that bites can be accurately recorded on the skin. There is an assumption that forensic dentists are good at identifying wounds and that they can identify who did the biting, too.

Unfortunately, it has been shown that at least 35 wrongful indictments and convictions have occurred because of bite mark analysis evidence.

Discredited by science, bite mark analysis still shows up in court

Forensic science, for the most part, is created by the police. It is used in support of law enforcement.

That’s problematic, because when the science doesn’t hold true, it isn’t always discounted right away.

Skin is not able to record teeth marks or other marks made by instruments clearly. It’s highly unlikely that you would be able to pull accurate evidence from the skin, because it is prone to bleeding and bruising. On the other hand, cartilage is better able to record patterns, but that’s not usually used in these analyses.

Bite mark analysis is grossly unreliable, which is why it should not be included in cases. Today, it’s suggested that experts in bite mark analysis should no longer make identifications based on the marks but instead consider excluding or including a person as a potential contributor when discussing them. In some cases, they should simply state that they are inconclusive.

Bite mark analysis can be false, and there is a wide margin of error. If it is used in a case, it is valuable to look into having that evidence removed.

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