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Accused murderer wins right to check source code of DNA testing kit

theregister.com

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Re: Accused murderer wins right to check source code of DNA testing kit

#481

Post by ALittleLight »

belorn wrote: post #421
Spivak wrote: post #265

Earlier quoted context omitted.

I like how this is considered a bad thing. Like we can’t let this guy point out that he’s being convicted by an unauditable black box that suddenly isn’t worth using if it has to stand up to scrutiny because then everyone would want to. The horror. Like I’m actually kinda shocked this is the reality. I would have assumed that DNA evidence would have some blessed methodologies and tools/algorithms, with a strict defin…

Here in Sweden, there is a legal practice that you can't find someone guilty based on DNA evidence alone. Probabilistic evidence is nice to point law enforcement in a direction, but there is always a risk of false positives. In this case we are also dealing with probabilistic genotyping involving DNA Mixtures with DNA from several individual contributors, and most likely degraded DNA. It is the tool the police can us…

Isn't all evidence probabilistic? What's an example of something that isn't?

Re: Accused murderer wins right to check source code of DNA testing kit

#482

Post by ALittleLight »

michaelmrose wrote: post #466
kenjackson wrote: post #456

Earlier quoted context omitted.

Who said they can’t back it up? The defendant claimed he needed to review it. The company presumably has done its own validation.

There is no reason to presume they did their own validation correctly absent proof of same.

Hopefully they have to have demonstrated some level of quality to be used as legal evidence in convicting someone. Although, I would hope "code analysis" is an infinitesimal part of the validation with the majority being real world end to end tests. (e.g. we can take 10,000 samples, divide them in two, mix them, then use our tool to pair up the samples with 100% accuracy).

Re: Accused murderer wins right to check source code of DNA testing kit

#483

Post by gwd »

acct776 wrote: post #450
MereInterest wrote: post #425

Earlier quoted context omitted.

Interesting. What does Swedish law consider non-probabilistic evidence? Even something like eye-witness testimony I would consider to be probabilistic, given how easy it is to manipulate memories, even unintentionally.

Clear videographic, use of a PIN that only the accused had access to, etc

How do you prove that only the accused had access to a PIN? Surely that's probabilistic as well?

Re: Accused murderer wins right to check source code of DNA testing kit

#484

Post by himinlomax »

unishark wrote: post #378
phire wrote: post #93

> The co-founder of the company, Mark Perlin, is said to have argued against source code analysis by claiming that the program, consisting of 170,000 lines of MATLAB code, is so dense it would take eight and a half years to review at a rate of ten lines an hour. First, the defence doesn't necessarily have to evaluate all 170,000 lines. They just need to find one buggy line which could potentially overturn the result.…

A lot of bashing over a vague third-hand quote without a source. In the very next paragraph they say: > The company offered the defense access under tightly controlled conditions outlined in a non-disclosure agreement, which included accepting a $1m liability fine in the event code details leaked. But the defense team objected to the conditions, which they argued would hinder their evaluation and would deter any expe…

> So it's a concern about IP protection for them.

For that kind of product, source code is not actually that valuable in itself; it's the standards compliance, reliability and trustworthiness. Most charitable explanation is that the vendor is clueless about what their value really is, least charitable is that they know exactly how fucked up their code is.

Re: Accused murderer wins right to check source code of DNA testing kit

#485

Post by mlindner »

Blikkentrekker wrote: post #476
belorn wrote: post #421

Earlier quoted context omitted.

Here in Sweden, there is a legal practice that you can't find someone guilty based on DNA evidence alone. Probabilistic evidence is nice to point law enforcement in a direction, but there is always a risk of false positives. In this case we are also dealing with probabilistic genotyping involving DNA Mixtures with DNA from several individual contributors, and most likely degraded DNA. It is the tool the police can us…

In the U.S.A., a man can be convicted upon the word of a single witness, even if the defence poked significant holes into the reliability of said witness. What can happen in the U.S.A. is that one lone man says “ I saw the defendant do it. ”; the defence attorney can point out that the witness was drunk at the time, that he has motive to lie, that he initially reported another story to the police and only later settl…

> What a shocking development that such would result into a criminal justice system where a defendant's race and gender plays such a factor.

It takes only one person in the jury to hang the jury. It's not a majority vote it's a unanimous vote.

Re: Accused murderer wins right to check source code of DNA testing kit

#486

Post by mlindner »

gidan wrote: post #223
nickodell wrote: post #158

Earlier quoted context omitted.

>My prediction: this firm will probably try to get removed from the case, rather than open source their shitty code. That isn't necessarily their choice. The prosecutors will make the decision about whether to withdraw the DNA evidence. They probably won't, given that they would need to give the defendant a new trial, which could lead to an accused murderer getting off. A bad look for any prosecutor. More to the poin…

That would be implying that the prosecutor would prefer taking the life of an innocent rather than having it hurt his career, making the prosecutor kind of a criminal.

That's not how prosecuters work in the US. Their goal is to win the case, not make the "right" decision. They'll spin evidence as hard as they can against the accused.

Re: Accused murderer wins right to check source code of DNA testing kit

#487

Post by Blikkentrekker »

mlindner wrote: post #485
Blikkentrekker wrote: post #476

Earlier quoted context omitted.

In the U.S.A., a man can be convicted upon the word of a single witness, even if the defence poked significant holes into the reliability of said witness. What can happen in the U.S.A. is that one lone man says “ I saw the defendant do it. ”; the defence attorney can point out that the witness was drunk at the time, that he has motive to lie, that he initially reported another story to the police and only later settl…

> What a shocking development that such would result into a criminal justice system where a defendant's race and gender plays such a factor. It takes only one person in the jury to hang the jury. It's not a majority vote it's a unanimous vote.

Bench trials are also required to be unanimous.

Methinks the U.S.A.-man often thinks that bench trials in other countries are done by a single juror; they are not and can range from three to twelve in how many professional jurors are required to reach a unanimous conclusion.

But this is not so much about lay fact finding vis-ǎ-vis trained fact-finding, but the rules of evidence.

Scotland also has jury trials, but does not permit that a man be convicted upon the word of a single witness; there must be further independent, corroborating evidence.

There are many other differences with, for instance, the Dutch system that guarantee a fairer trial. One very big one is that in the Netherlands both the defence and prosecution have one groundless appeal; either side if it not agree with the verdict can demand a fresh new trial with different jurors once. — this obviously reduces flukes of justice.

The other is far stronger rules of evidence and more consistent rulings. Juries are very fickle and legal experts rarely know what verdict they will return based on the evidence they saw before them; whereas with trained jurors, their verdict is often similar with the same evidence given to them.

Indeed, one might argue that the practice of plea bargains, which would be considered unconceivably unethical in most jurisdictions, are actually the saving grace, as they permit stability to this otherwise fickle system as the negotiations between both parties are more reproducible given the same evidence, than fickle juries.

Re: Accused murderer wins right to check source code of DNA testing kit

#488

Post by kenjackson »

michaelmrose wrote: post #466
kenjackson wrote: post #456

Earlier quoted context omitted.

Who said they can’t back it up? The defendant claimed he needed to review it. The company presumably has done its own validation.

There is no reason to presume they did their own validation correctly absent proof of same.

I think this is the crux of the problem. If the defendant gets to decide when validation is sufficient then should they ever say it is sufficient?

Re: Accused murderer wins right to check source code of DNA testing kit

#489

Post by hutzlibu »

vmception wrote: post #386
hutzlibu wrote: post #362

Earlier quoted context omitted.

"Yes, that middle zone (that most of us probably live in) is terrifying" More terrifying than the bottom where you got nothing to loose? I doubt it. Otherwise, why be afraid of it?

I would say just because of the energy and sacrifices used At the bottom you don't have to pretend that the circumstances will improve, and there is some freedom associated with some approaches to that. Careers don't need to have continuity, I know many people in hospitality and service industry whose vacation policy is saving and quitting one restuarant, travelling, and getting another job at a different restuarant…

"At the bottom you don't have to pretend that the circumstances will improve"

Well, sorry, but I would also say, you don't know what you are talking about.

First of all, there is no bottom at the bottom - you can always fall deeper, until there is no more escape than suicide. I know people who did.

What you maybe mean, are people who don't care abobut materialism and live with little to no money by their choice. I lived with those people for quite some time and it was fun.

When you are young and healthy and on your own, you don't really have to worry about a lot of things. I worried about my backpack with my laptop and that was it. I slept in a tent or under the stars or wherever. When the money was gone, there were always places or ways to get food. Work a little, travel a little. Easygoing.

But now I have a family. Now I cannot not have money.

Re: Accused murderer wins right to check source code of DNA testing kit

#490

Post by astura »

hastradamus wrote: post #110

The co-founder of the company, Mark Perlin, is said to have argued against source code analysis by claiming that the program, consisting of 170,000 lines of MATLAB code, is so dense it would take eight and a half years to review at a rate of ten lines an hour. This is hilarious. As if you need to read every damn line and you can’t skip blank lines? You can skip whole files that aren’t relevant. Weak excuse

This is a stupid "argument", I've personally participated in an audit of a program that has 5-6x as many lines of code.
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