Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Bad science and bad statistics in the courtroom convict innocent people

scientificamerican.com

Post reply on HN
Print view View original

41–50 of 205 posts

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

#41

Post by tonyedgecombe »

10000truths wrote: post #31
WalterBright wrote: post #29

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 off…

Do you have a link to the case details? At the very least, there has to have been some additional evidence to convict, even if circumstantial. I find it hard to believe that someone can be ruled guilty of a crime as serious as rape based solely on the plaintiff's testimony.

Here is an example: https://www.bbc.co.uk/news/uk-66513959

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

#42

Post by graphe »

klyrs wrote: post #14
graphe wrote: post #7

Earlier quoted context omitted.

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.

This is magical thinking. We know the guy was bad so we locked him up for a crime. We don't know if we pinned the right crime on him or not, but he's locked away safely now so he must be bad. If this is your genuine belief, it begs the question: why are Americans, on average, such terrible people when compared to other first world citizens?

You don’t just decide to lock someone up for a crime. Police gather evidence, give it to a prosecutor, the prosecutor makes a case (or not) and they will either go to trial or plea, then it’s in the hands of a jury or judge.

Claiming guilt to plea down to avoid a case is a problem, but that isn’t the case you’re making. There’s nothing magical about criminal prosecution.

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

#43

Post by 2devnull »

10000truths wrote: post #31
WalterBright wrote: post #29

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 off…

Do you have a link to the case details? At the very least, there has to have been some additional evidence to convict, even if circumstantial. I find it hard to believe that someone can be ruled guilty of a crime as serious as rape based solely on the plaintiff's testimony.

>I find it hard to believe

I find it hard to believe you find it hard to believe. :) There’s a cliche term for such cases, “he said/she said” and they are not at all uncommon.

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

#44

Post by moate »

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.

[flagged]

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

#45

Post by rpmisms »

gruez wrote: post #35
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…

>I’m reminded of the Rittenhouse trial where the prosecutors had a technician massage a still from a video for hours until some very tiny collection of pixels, enlarged from the original by quite a bit, were arranged in such a way that they said demonstrated Rittenhouse initiated aggression against the first man he shot. Is there an article with more on this?

Didn't find any with a cursory search, but the full trial is available on YouTube, and this particular argument is incredibly frustrating to watch. The judge should never have allowed it in.

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

#46

Post by WaitWaitWha »

This a bit misaligned, blame shifting. I will be the first to admit there are unscrupulous, fame seeking, and overzealous expert witnesses out there. But, there are mechanisms in the courts to filter most of them out. I just think it is not done for money, time, career, or political reasons.

I have seen this fail both in the adversarial (e.g., US) and elsewhere in inquisitorial (e.g., EU) court systems.

In the adversarial courts, time and time again I watch lawyers refuse to hire expert witnesses for their own side because .

Overall, there is also the opportunity for a voir dire of the expert witness. Failure to perform that is again lawyers' fault.

So, who is to blame for all the mistakes? Yes, all of them.

Final note regarding experts in court, specifically around professional expert witnesses - there is a racket in the industry where new-comers are kept out. The expert witness industry does some gatekeeping not only for expertise, but for retiring law enforcement in some jurisdictions. For example, in some US states a digital forensics expert required to be a licensed Private Investigator, unless former law enforcement. The PI licensing requirement are completely irrelevant for the expert witness role.

Personal anecdotal experience - Lawyer thinks he is technologists, refuses to hire expert witness, begs expert to come middle of the case. Lawyer hires cheapest expert, opposing expert makes haggis out of cheapest expert.

Funniest one was where in a small court the State's expert start going off on some cockamamie ideas about transference. The opposing expert was an instructor and had one of her classes in court to learn. The class burst out laughing, and the judge had to gavel. When she got on the stance, it was just glorious, torturous evisceration.

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

#47

Post by qingcharles »

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.

OK, having spent practically 10 years inside and having helped 1000s of people with their cases, here's my single-person perspective: at least 95% of the people locked up are guilty of something related to their charges. The justice system isn't completely off-kilter.

My main issues were that a) many people were overcharged (i.e. charged with extra crimes they were not guilty of) simply to obtain a plea deal; b) often police/prosecutor/judicial misconduct was used to get the defendant into the justice system and convict them; c) the sentences are often out-of-whack compared to the crime; d) jails and prisons generally offer very little value and rehabilitation.

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

#48

Post by pc86 »

graphe wrote: post #36
WalterBright wrote: post #29

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 off…

This indicates that the jury/judge also failed the innocent man. What would have saved him? Are these cases relics before dna? Would it happen again today?

I think it depends on your definition of "failed." An eye witness said it was him. He likely didn't have an alibi that could have withstood an eye witness pointing at him and saying "he did this." Had he been at a convenience store on camera, or some other incontrovertible thing, it would have most likely turned out differently.

I'm not sure how a reasonable judge or jury would have come to any other conclusion given what little we know about this third-person retelling of a case so I don't think they "failed" him at least in the way I typically think of that word being used in these contexts.

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

#49

Post by graphe »

moate wrote: post #44
graphe wrote: post #7

Earlier quoted context omitted.

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.

[flagged]

[flagged]

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

#50

Post by qingcharles »

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…

And it completely depends on what you mean by innocent.

A lot of cases are won by defendants, who after spending years in pretrial, find the prosecution did not have enough evidence to convict them.

I've been witness to some far-out jury cases where the defendant was massively guilty but the jury acquitted for some reason. That's why I would often recommend a jury trial in a lot of cases simply because juries have such a high randomness attached to them.

Post reply on HN