Cops and pseudoscience go together like chocolate and peanut butter.
For more examples, see “bite mark analysis,” “911 call analysis,” “blood spatter analysis,” roadside drug testing with known false-positives, and even fingerprints (once the gold standard) have up to a 20% error rate.
And that’s not even getting into how their methodology is exactly backwards: they have a claim that they set out to prove, but do no work to disprove what they already believe.
Blood spatter analysis isn’t quite as nonsense as the rest. There are definitely factual conclusions that can be made based on where blood is found and how it is distributed or shaped.
Polygraph tests are an interrogation tool. While the “results” they produce directly are nonsense, they can be used as a lever to pressure a suspect to confess to a crime - with disregard as to whether they actually committed said crime. People who undergo polygraphs are also known to unload new information immediately after the “test” is over.
Remember, police are allowed to lie to you; you are not allowed to lie to the police. Shut the fuck up. Lawyer.
The reliability of bloodstain-pattern analysis has never been definitively proven or quantified, but largely due to the testimony of criminalist Herbert MacDonell, it was steadily admitted in court after court around the country in the 1970s and ’80s. MacDonell spent his career teaching weeklong “institutes” in bloodstain-pattern analysis at police departments around the country, training hundreds of officers who, in turn, trained hundreds more.
While there is no index that lists cases in which bloodstain-pattern analysis played a role, state appellate court rulings show that the technique has played a factor in felony cases across the country. Additionally, it has helped send innocent people to prison. From Oregon to Texas to New York, convictions that hinged on the testimony of a bloodstain-pattern analyst have been overturned and the defendants acquitted or the charges dropped.
In 2009, a watershed report commissioned by the National Academy of Sciences cast doubt on the discipline, finding that “the uncertainties associated with bloodstain-pattern analysis are enormous,” and that experts’ opinions were generally “more subjective than scientific.” More than a decade later, few peer-reviewed studies exist, and research that might determine the accuracy of analysts’ findings is close to nonexistent.
Blood spatter analysis isn’t quite as nonsense as the rest.
If blood is found underneath an object, you know that the blood got there first, and the object second. If you find a drop of blood among a bunch of fine mist, you may be able to predict that the fine mist is blood from a victim after a gunshot, while the drop might be from someone else, possibly the perpetrator.
Of course there are other observations which are misinterpreted, but the fact remains that blood spatter follows the laws of physics; therefore, it is possible to discover factual information from observing it.
Sure, but that’s not what police refer to when they talk about blood spatter analysis. I’m not saying it’s impossible to get good evidence from the location of blood; I’m saying that the bullshit they do around drop size and splatter patterns does not have any evidence to support it.
Edit: in other words, they want the credibility of science without doing the hard work of peer-review or falsification.
Cops and pseudoscience go together like chocolate and peanut butter.
For more examples, see “bite mark analysis,” “911 call analysis,” “blood spatter analysis,” roadside drug testing with known false-positives, and even fingerprints (once the gold standard) have up to a 20% error rate.
And that’s not even getting into how their methodology is exactly backwards: they have a claim that they set out to prove, but do no work to disprove what they already believe.
Blood spatter analysis isn’t quite as nonsense as the rest. There are definitely factual conclusions that can be made based on where blood is found and how it is distributed or shaped.
Polygraph tests are an interrogation tool. While the “results” they produce directly are nonsense, they can be used as a lever to pressure a suspect to confess to a crime - with disregard as to whether they actually committed said crime. People who undergo polygraphs are also known to unload new information immediately after the “test” is over.
Remember, police are allowed to lie to you; you are not allowed to lie to the police. Shut the fuck up. Lawyer.
From ProPublica:
If blood is found underneath an object, you know that the blood got there first, and the object second. If you find a drop of blood among a bunch of fine mist, you may be able to predict that the fine mist is blood from a victim after a gunshot, while the drop might be from someone else, possibly the perpetrator.
Of course there are other observations which are misinterpreted, but the fact remains that blood spatter follows the laws of physics; therefore, it is possible to discover factual information from observing it.
Sure, but that’s not what police refer to when they talk about blood spatter analysis. I’m not saying it’s impossible to get good evidence from the location of blood; I’m saying that the bullshit they do around drop size and splatter patterns does not have any evidence to support it.
Edit: in other words, they want the credibility of science without doing the hard work of peer-review or falsification.