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Bad science and bad statistics in the courtroom convict innocent people

scientificamerican.com

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Re: Bad science and bad statistics in the courtroom convict innocent people

#21

Post by tiahura »

causal wrote: post #10

Note that proportionately few of our federal judges have spent any time as public defenders, and a disproportionately high number have served as prosecutors. Jackson is the first supreme court justice to have served as a public defender, whereas 3 other justices have been prosecutors. Prosecutors are incentivized to get convictions, and that slanted thinking could easily be carried on to the bench. [1] https://www.pb…

Being primarily a civil attorney, I'm well aware of the disproportionate number of former prosecutors on the bench. A couple of points:

1. Most prosecutors are liberals. It's not like right wing law students go looking for jobs in prosecutor's offices. I can't think of any from my class way back when.

2. The problem is more that judges and prosecutors are old colleagues. The slant is that they all know the defendants are guilty. There's so much crime, and aversion to losing trials, that (unless politics is involved) prosecutors tend to only bring cases where the defendant is clearly guilty. They like shooting fish in a barrel. If they find that there are problems with a case they tend to let the defendant get continuance after continuance until the case just goes away on its own.

Re: Bad science and bad statistics in the courtroom convict innocent people

#22

Post by s1artibartfast »

graphe wrote: post #7
causal wrote: post #5

It would be hard to really know, but I'm curious what percentage of the total US prison population is innocent. Per capita prison rate is still around 5 in 1000 according to Wikipedia, which is very high for the developed world.

Innocent meaning they didn’t do the specific crime, or innocent as in someone with a clean record that was railroaded? If you’re looking for the criminal that killed a bunch of people but not that specific case it’s not that uncommon. If you’re looking for a squeaky clean guy that was there at the wrong place at the wrong time it’s very rare. Most criminals are repeat offenders.

I believe, and I think the data supports, that the US prison population is due to the number of laws we have, and the harshness of our penalties.

A false conviction rate of a few percent does not explain an order of magnitude level differences in incarceration between countries.

I think an interesting question is what portion of the US population would be incarcerated if the totality of our laws were applied to everyone

Re: Bad science and bad statistics in the courtroom convict innocent people

#23

Post by gjsman-1000 »

Lord-Jobo wrote: post #20
adamsb6 wrote: post #17

Even photo and video evidence suffers from courtrooms that don’t understand how nearly all cameras will record and encode images. JPEG encoding (and thus MPEG encoding) takes 8x8 blocks of pixels and represents them as a discrete cosine transform. In a very real way these pixels don’t actually exist. If your video evidence relies on such a small portion of MPEG encoded video, you can easily mislead a jury to convicti…

This is one of the better litmus tests to see if the expert witness is knowledgeable in the field, and more importantly, up-to-date on the tech. some really smart but definitely older expert witnesses will fumble this very hard. Its not like those kinds of processes, the "enhancing" filters, are inherently bad or inadmissible, you just have to be clear with the judge and jury what the hell is actually happening.

This also came up in the Johnny Depp trial, where evidence was challenged and there was a long discussion about whether a video that had been shared over AirDrop was admissible, or whether that should be considered tampering, due to the possibility of it being re-encoded / compressed (which is a theoretically possible concern, as doesn't iPhone record in HEVC but change it to H.264 when shared with people?)

Re: Bad science and bad statistics in the courtroom convict innocent people

#24

Post by csours »

tiahura wrote: post #16

The article doesn't prove anyone was actually innocent, only that dodgy science was admitted. In the highlighted case, I'm assuming the victim's multiple identifications of Odom as the perp was also fairly persuasive to the jury.

Have we discovered how to prove a negative and I missed it? Or do we still have to look at the balance of evidence?

In other words: in most justice systems, the prosecution must produce evidence of guilt, they hold the burden.

It's also very important to know that (in the US justice system), evidence of innocence is not persuasive to appellate courts; they are looking for abuse of process.

---

Now, cognition is a different matter altogether. When something terrible has happened, the human mind looks for the cause, specifically for the person who caused the terrible event.

Sometimes, there is a person who did a crime - when someone is shot, that is generally treated as a crime.

But sometimes sick people die. Sometimes infants fail to continue breathing. Sometimes wildfires burn a town and kill people. Sometimes viruses jump from (non human) animals to humans.

In other words, in human cognition, satisfaction is more important than truth. Scientific truth is a framework whereby we delay our satisfaction with an answer, using specific tools that are socially accepted in that field of study.

Re: Bad science and bad statistics in the courtroom convict innocent people

#26

Post by graphe »

If we accept that court cases will have a non zero error rate, what rate are we comfortable with? Court cases are irregular, judges, the jury, the experts and the type of prosecution matters. Are we more comfortable with different crimes at different rates?

In the US, you’re presumed innocent (in the eyes of the law) and many in cases the law can tip the balance over a technicality, such as fruit of the poisoned tree and inability to admit some evidence that would be essential in a layman’s eyes. How would a court be robust against problems such as biased experts, juries and judges? Would we be more comfortable with a lower or higher than average conviction rate? Is the problem the prisons?

Re: Bad science and bad statistics in the courtroom convict innocent people

#27

Post by mistrial9 »

graphe wrote: post #15
Zigurd wrote: post #11

Earlier quoted context omitted.

Most businesses create and cultivate repeat customers from specific target markets. The US prison industrial complex is adept at this.

What is the conclusion you’re making?

it is a revolving door in real ways

Re: Bad science and bad statistics in the courtroom convict innocent people

#28

Post by causal »

tiahura wrote: post #21
causal wrote: post #10

Note that proportionately few of our federal judges have spent any time as public defenders, and a disproportionately high number have served as prosecutors. Jackson is the first supreme court justice to have served as a public defender, whereas 3 other justices have been prosecutors. Prosecutors are incentivized to get convictions, and that slanted thinking could easily be carried on to the bench. [1] https://www.pb…

Being primarily a civil attorney, I'm well aware of the disproportionate number of former prosecutors on the bench. A couple of points: 1. Most prosecutors are liberals. It's not like right wing law students go looking for jobs in prosecutor's offices. I can't think of any from my class way back when. 2. The problem is more that judges and prosecutors are old colleagues. The slant is that they all know the defendants…

Thanks for that insight. My discomfort is with the notion that they could know that the defendant is guilty- sure there may be some obvious cases, but I do not trust most humans to differentiate their intuition from hard evidence.

Re: Bad science and bad statistics in the courtroom convict innocent people

#29

Post by WalterBright »

I read about a case once where a man was convicted of rape. The evidence was that the rape was done face-to-face with the victim, and the victim positively ID'd him. How could she not, when she was face-to-face with him? It was a slam dunk.

After some years in prison, the convicted person managed to get a DNA test, which proved he was not the rapist. How could this be?

It turns out the DNA matched a convicted sex offender who had, in the meantime, died in prison. A picture of him showed that he looked just like the falsely convicted man.

The victim, to her credit, profusely apologized for mis-identifying him, but she acted in good faith.

Re: Bad science and bad statistics in the courtroom convict innocent people

#30

Post by causal »

Lord-Jobo wrote: post #19
causal wrote: post #5

It would be hard to really know, but I'm curious what percentage of the total US prison population is innocent. Per capita prison rate is still around 5 in 1000 according to Wikipedia, which is very high for the developed world.

This is an obviously tough subject to get precise data on, but dark figure analysis and innocence project data indicates that the CONVICTED innocent percentage is 1-3%, i have seen individual studies peak at 7% but those are outliers and not likely to be the real number. this seems really good until you realize its 20,000-140,000 people in prison right now. that are innocent. and it gets REALLY bleak when you look at…

Thanks for bringing that data. And yeah, half a million is a staggering number if true.
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