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

theregister.com

271–280 of 520 posts

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

#271
post #34

Wouldn't this set a precedent to eventually force any forensic software to become open source?

Not per-say, though it certainly affords it the same level of scrutiny. Which may well be a win as open source already has that. However, even open source has bugs that pass scrutiny as many CVE's can attest, so whilst a code review may find nothing wrong, that in itself could be used by a lawyer to create reasonable doubt, if the lawyer is good.

[deleted]

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

#272
Interesting that they're putting so much focus on the DNA piece, since the actual crime was witnessed by a police officer and there is circumstantial evidence tying the suspect to the weapon (it was found along the path they used to flee from the scene).

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

#273

It's an important development. Forensic labs and companies are expert witnesses with black box processes and the incentive to protect the authority of their profession. They are as likely to lie as any other witness. Perhaps even moreso. "Those arguing on behalf of the defense cited past problems with other genetic testing software such as STRmix and FST (Forensic Statistical Tool). Defense expert witnesses Mats Heim…

DNA testing should be double blind. I have no idea if it is.

Sample contamination can be arranged before sent to the lab though.

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

#274

Earlier quoted context omitted.

Testify does not equal independently certified. Also, double-blind testing is not really subject to faking. Its the standard of science. Responses to my comment are all around 'how it is now' which seems not to be very reliable. A responsible testing/certification process would address that.

You've just moved the goal posts from someone who can be crossed in court to someone who can't, which is worse, because then you have now way of verifying that the "independent" certifier is actually independent or that the certification was properly done. You still need to allow the "independent certification" to be examined in court to validate both the independence and the certification. The means testimony on the…

The skepticism has to end somewhere. Else ever court case becomes an infinite regressing into doubting the foundations of everything.

Of course self-certification is not the best. To bring up that straw man (as most of these posts do) is not advancing the conversation.

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

#275
post #160

Earlier quoted context omitted.

There are countries where the job of the prosecutor is to uncover the truth, not to convict someone at all costs: https://en.wikipedia.org/wiki/Inquisitorial_system

Conviction rates are surprisingly high in a lot of the first world.

I’m not sure what conclusion we should draw from that isolated fact. It can mean that people are convicted on too weak evidence, and it can mean that people are only put on trial when the evidence already is very strong.

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

#276
For the Europeans among us, I would like to remind you that there's an initiative to opensource all publicly funded code

https://publiccode.eu/

If you care, add your signature and vote for a party during the next elections that considers opensource at least somewhat important.

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

#277
post #82

I have worked with MATLAB code with 20,000 lines of code. Only over the past years, OOP and unit-testing has become properly available and usable. My guess is that this 170,000 lines are written in the old procedural way (also for performance reasons) and are full of bugs, also thanks to the lack of supporting tools. Most likely, this grew out of a research prototype that just worked too well to be reimplemented in a…

I wonder if bug tracker and other reports would be part of discovery in this case.

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

#278

Earlier quoted context omitted.

Compile it, run it with the same inputs the prosecution claims was provided, and see if you get the same result. That's sorta the point of computers, right? Same inputs on the same program, same output?

> Compile it, run it with the same inputs the prosecution claims was provided, and see if you get the same result. That's sorta the point of computers, right? Same inputs on the same program, same output? One difficulty here is that the input is a real world effect. That means the answers are rarely exactly the same. The last time I looked, breathalyzers have a ~50% margin of error. So if you blow a 0.06, your BAC is…

>The last time I looked, breathalyzers have a ~50% margin of error

Source on this? I know the portable ones are like this, but I thought the actual court-admissible ones are more accurate, and the calibration procedures need to be followed to get a conviction. Also, FSTs are quite good for preliminary screening, a proper HGN test especially. And if you ask for a blood test, they are required to give you one and consider it in court.

Cops have no incentive to make people who aren't drinking take FSTs or the breathalyzer, its just a waste of their time. They don't want to be bothering normal people, they want to be taking real dangerous and irresponsible drivers off the road. You survive by not drinking before driving, or having a DD, its really not that hard.

Implied consent is the reason for the tests, and you agree to it when you sign for a license. And I think its a worthwhile tradeoff if it actually works to reduce DUI deaths.

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

#279
post #194

Earlier quoted context omitted.

I'd get an expert witness in there to testify basically that. I also don't think you should code anything mission critical like this in Matlab. It's a decent language for prototyping, not for production.

> I'd get an expert witness in there to testify basically that. Sounds really expensive.

I’ll do it for free

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

#280
post #149

Earlier quoted context omitted.

No, the question is what is the incentive for lying and claiming guilty? Do prosecutors choose different labs?

Of course prosecutors will favour expert witnesses that will help them get convictions. Why isn’t that obvious?

Sometimes the expert witness is in the department's own lab. It seems a tautology that they will favor conviction. Every officer bringing in evidence is begging "Give me something I can use to get this scumbag!" The pressure to fudge is enormous.

A fairly simple step is to certify equipment independently, and to do blind testing (one sample is provided from evidence; another by an independent unrelated source). Of course this costs more, but anything else is effectively an experiment without a control.

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