Study on Bloodstain Pattern Analysis Finds 'Conclusions Were Often Erroneous' *graphic*

[Nevilledog]

Last edited Fri Jun 11, 2021, 06:02 PM - Edit history (1)

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CJ Ciaramella
@cjciaramella
New: the largest-ever study so far on the accuracy of bloodstain pattern analysis found "conclusions were often erroneous and often contradicted other analysts"

Study on Bloodstain Pattern Analysis Finds 'Conclusions Were Often Erroneous'
Bloodstain pattern analysis is one of several forensic techniques that has come under scrutiny in recent years for its lack of established error rates.
reason.com
12:25 PM · Jun 11, 2021

https://reason.com/2021/06/11/study-on-bloodstain-pattern-analysis-finds-conclusions-were-often-erroneous/

The largest-ever black-box study on the accuracy of bloodstain pattern analysis (BPA), a widely used forensic technique, has found concerning error rates and disagreement among analysts.

The study, published in the August 2021 volume of Forensic Science International, is the most rigorous attempt so far to measure the accuracy and reproducibility of BPA, in which analysts interpret bloodstains at crime scenes.

"Our results show that conclusions were often erroneous and often contradicted other analysts," the report found. "Both semantic differences and contradictory interpretations contributed to errors and disagreements, which could have serious implications if they occurred in casework."

For the study, researchers collected 192 examples of blood spatters from controlled samples and actual casework and presented pictures of them to 75 practicing BPA analysts for classification.

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[ZZenith]

1. Graphic warning might be a good idea in the headline.

Such images can really trigger the ole PTSD.

[milestogo]

2. Well they should have consulted with Dexter.

He made it seem very precise.

[bahboo]

3. hah...first thing that came to my mind as well...

[obamanut2012]

4. Hair and most fiber analysis, bullet/casing analysis, and this -- all junk science

People were sent to Death Row (and still are) because of junk science.

[Disaffected]

6. Eye witness testimony

is also sometimes unreliable, not to mention polygraphs. Pray hard that you are never wrongly accused of a serious crime...

[Midnight Writer]

7. And bite mark matching.

[kskiska]

5. That was significant in the Sam Shepard guilty murder verdict in 1954

and many, many capital punishment cases.

[Silent3]

8. There's a lot of bad science and pseudoscience in arson forensics too

https://www.abajournal.com/magazine/article/long_held_beliefs_about_arson_science_have_been_debunked_after_decades_of_m

[Mr.Bill]

9. My pet peeve is letting

a dog essentially sign a search warrant.