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This Impenetrable Program Is Transforming How Courts Treat DNA Evidence (wired.com)
mirandakatz writes: Probabilistic genotyping is a type of DNA testing that's becoming increasingly popular in courtrooms: It uses complex mathematical formulas to examine the statistical likelihood that a certain genotype comes from one individual over another, and it can work with the subtlest traces of DNA. At Backchannel, Jessica Pishko looks at one company that's caught criminal justice advocates' attention: Cybergenetics, which sells a probabilistic genotyping program called TrueAllele -- and that refuses to reveal its source code. As Pishko notes, some legal experts are arguing that Trueallele revealing its source code 'is necessary in order to properly evaluate the technology. In fact, they say, justice from an unknown algorithm is no justice at all.'
I think it is very reasonable to ask access, covered by NDA, to a source code when such code is used to produce results for criminal prosecution. Unless they can show independent third-party validation of their tool.
We have seen issues with red light cameras, we have seen issues with labs doing drug testing on hair, we have seen child abuse panics from psychology "experts". Both methods and experts have to be open for independent, impartial validation. Otherwise they are no better than a duck test.
As Terry Pratchett wrote somewhere: "Evidence means 'that what is seen'". Nuff said.
Paaia
Computers cannot lie, unless programmed to do so.
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A lot of expert witness testimony comes down to a judgement call -- "In your opinion, as someone who has been working in this field for 20 years, how confident are you that these signatures / bullet marks / fingerprints / DNA match?" That's the result of an algorithm that you can't examine either, and has at least as much opportunity for being corrupted by unconscious prejudice or outright bribery as a piece of software.
TCP: Why the Internet is full of SYN.
"justice from an unknown algorithm is no justice at all"
...
A successful conviction may be legitimately tipped by accurate checked evidence, in this case DNA
But justice is not a matter of technical facticity. It is withholding something from a party that they deserve.
The evidence may help identify discrepancies between the two, but it is a major conflation to substitute that with justice.
Jurors and judges need to know what the probabilities are. Remember, in a criminal trial, the standard for evidence is "beyond a reasonable doubt." Sending people to prison for life or even to death row based on flimsy evidence is unacceptable.
This isn't to say that it hasn't happened before -- Cameron Todd Willingham was executed in Texas on the testimony of an "arson expert" with no formal training in the field.
The code should be evaluated or the tool should be banned from court. The company doesn't like it? Too bad. They don't have to sell to the forensic lab/law enforcement market.
You have the right to face your accuser, which includes examining the evidence against you. This is secret evidence. It amounts to "because we say so", and should not be tolerated.
A software bug you're not permitted to look for could send you to jail. At least with a human expert witness you can cross-examine them.
One thing is having access to the source code and a completely different story is properly analysing it. When dealing with something as complex as (probabilistic!) DNA sequencing, it seems quite clear that the most sensible way to validate the program is actually using it. Set up a proper benchmark with a relevant number of samples and confirm whether this (+ any other) program works exactly as expected. This would also be an excellent way to objectively assess its accuracy.
Custom Solvers 2.0 = Alvaro Carballo Garcia = varocarbas.
Expert judgement can be countered by other experts. Here we are being presented with something as a "Fact". There is no way to dispute it and there is no way to verify it which is what people are having a problem with.
Expert judgement can be countered by other experts. Here we are being presented with something as a "Fact". There is no way to dispute it and there is no way to verify it which is what people are having a problem with.
Questioning expert's qualifications is fair game in trials. If you can demonstrate that expert is not impartial, you can largely mitigate their testimony.
How do you question algorithm like if (1) = Guilty; other than code review?
All computers are programmed to lie, either through mistakes or intentional. You will never get away from this because computers are programmed by humans and our creations will always suffer from our own errors and misdeeds.
Please point to this model and indicate where it shows your precise location will be under 10' of water by now. Either that or admit you are full of shit and a liar.
A lack of evidence of this "model" will indicate you are a liar whether you respond or not.
Well it shouldn't be accepted as fact. Ideally the courts would instruct the jury to treat the software's output as similar to a human being saying, "This is my expert opinion." You can submit your own software's "opinion" as evidence as much as you can get your own expert human to testify on your behalf.
It is true that you can't cross-examine it; but ideally, that should make the software less reliable. If you had an expert who, upon cross-examination, always responded, "I don't know, it just seems that way", then he wouldn't have much credibility. Ideally, software that can't justify its "opinion" should be treated the same way.
I have said "ideally" here several times, recognizing that it may well be the case that this isn't how people actually think. But I think a more constructive response to this misplaced trust is to help inform courts and defense lawyers more clearly (who should in turn inform the juries).
TCP: Why the Internet is full of SYN.
You get to ask an expert witness why their opinion is what it is, and if they answer "I'm not telling," their credibility is shot and there's a good chance their testimony will be thrown out. This software is an expert witness that nobody has any reason to believe giving testimony damning a person and then refusing to explain why but maintaining credibility. Analyzing whatever algorithm the software uses would be like questioning the witness, which is your right as a defendant in the USA, and keeping it hidden is literally denying you that right.
I've done some genomic work, during the Human Genome Project. I had to step away from the work due to my concerns about the lack of quality. The analysis software of the data, to assemble longer genesic fragements for testing and verification, was so very very poor that all the scientists learned to ignore the analysis and order longer sequence manually, by eyeballing it with their personal experience. It was hideously expensive to do this constantly, especially with the amount of sequences to sample and test and which came back "does not work". Part of the result was that, because they were probing in the dark, they got far more false positives that had to be tested later, as part of an even longer or overlapping sequence, that even *that* data was unreliable.
We have *had* crime labs falsify evidence, with cases like https://www.cbsnews.com/news/a... . Without the ability to verify the provenance of the data, of the results, and of the analysis tools, the DNA analysis can be far too easy to falsify. It should be as verifiable as the scales used to measure the weight of drugs, or the spectrographic analyzer and its software.
What you're describing is exactly why experts frequently have their credibility challenged and why they need to provide the means by which to verify their credentials. The problem here is that they're providing no means by which to establish or confirm the credibility of the algorithm, and they know that doing so doesn't harm them as it would with an expert witness.
Imagine if the prosecution put an "expert" on the stand who testified how the prosecution wanted, but when the defense attorney asked where the "expert" went to school, where they worked, or how long they had been practicing, the "expert" refused to answer those questions and instead asked the jury to simply trust their "expert" opinion. They'd be laughed out of the court room, since the jury wouldn't know whether the "expert" was actually an expert or just a guy off the street. And that's how it should be.
Unfortunately, refusing to provide a means by which the credibility of this algorithm can be ascertained doesn't elicit the same response. Machines are commonly viewed as unbiased, logical, and factual, so while a human's refusal to allow their credentials to be verifiedwould be an immediate red flag, with a machine it doesn't mean much to most people. People are accustomed to thinking that algorithms produce factual results that can be taken at face value.
That's a problem when it comes to things that need to be verifiable, whether it's evidence in court or votes in an election.
You can't handle the truth [insert full quote here]
but anyway this should not be admissable in court until the source code (with needed toolchain) has been vetted by the Oldest and Crankiest Qualified persons they can find.
(does this have a bias as to which "race" it comes up with?? will it pop certain trait markers more often??)
Give Americans more credit. It's more likely to be
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
It is different in that you can challenge an expert witness with your own witness. How can you challenge an algorithm that no one really knows? Considering that the FBI has used flawed statistics in DNA matching for a decade, this is not the first time that there are issues with how forensic science is done.
Well, there's spam egg sausage and spam, that's not got much spam in it.
As a programmer I can assure you that I am infallible and perfect. My superiority is the reason I am a programmer and most people are not.
“Common sense is not so common.” — Voltaire
DNA probabilistic methods like this can do 3 things but can only be use to do one of them at a time. They can eliminate an accused, they can can eliminate all but one person from a predetermined sample of people to find the guilty person, or they can give the police a potential list of suspects. They CANNOT be used to do both of the last two. If I have a small partial DNA sample there will be multiple people in the world that it will match. If the police then just round up the first person that they find who matches and say oh the probability of a match this close is one in 300 million. Well no, if there were 300 million permutations and you looked in a population of 300 million people I would expect you to find a match (well at least 1 -1/e times) .
Well it's only be ~10 years since the Inconvenient Truth. I'm not sure what "near future" mean. If that means 1 year to you or 50 years to the rest of us. (I think his film was aiming at the year 2100, but I don't recall exactly).
Here's an example, some islands are completely covered by water at high tide. http://theconversation.com/sea...
The most up to date information has projections range from 0.2 meters to 2.0 meters (0.66 to 6.6 feet) of sea level rise in the next 100 years. [Melillo et al., 2014]. And that's the thing about science, you'll find that it is never 100% accurate and if you look back to previous theories and predictions can be embarrassingly inaccurate. But the scientific method generally leads to better answers through many iterations of models, research and theories.
Al Gore's 20 feet rise greatly exceeds the most conservative models, as you've already noted. On the other hand if all the ice covering Antarctica, Greenland, and in mountain glaciers around the world were to melt, sea level would rise about 70 meters (230 feet). That's the far extreme of what could be done with the matter available on Earth, it's not at all likely. (maybe if the Earth's axis tilted to expose the poles? Or maybe if 10's of thousands of years went by and we acquired an atmosphere like Venus that make air temperature nearly uniform across the planet, including the poles?)
“Common sense is not so common.” — Voltaire
Well it shouldn't be accepted as fact. Ideally the courts would instruct the jury to treat the software's output as similar to a human being saying, "This is my expert opinion." You can submit your own software's "opinion" as evidence as much as you can get your own expert human to testify on your behalf.
One of the requirements for presenting expert testimony is that you have to provide all of the materials that the expert used in forming their opinion. If the results of some software were treated as an expert opinion, the "materials relied upon" would almost certainly include the source code. It may even make the programmers, as the source of those materials, subject to being deposed about how they developed the software.
Whether it does or not doesn't matter as long as it isn't reviewed, because it will certainly be challenged on these grounds or at the very least you'll see the relevant pressure groups cry foul, whether or not it is.
This alone means that this MUST be reviewed before even thinking about considering it as admissible evidence.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
You brought up a good point.
So the counter would be to write a program that accepted the same physical evidence data and simply returned whatever answer the defense wants.
whois gawk date unzip strip find touch finger mount join nice man top fsck grep eject more yes exit umount sleep dump