Also, just curious, have they been discredited as in that double-blind trials show no more than a 50/50 chance of being correct (i.e., flipping a coin)? Or is it that a high enough percentage of people will fail them even if innocent, or pass them even if guilty?
The thing I don't like about them is the method of reading them, where it is up to the subjective judgment of the examiner. That is, there isn't an algorithm that can be written down so that, for example, an untrained person or computer program can read it (and therefore be subjected to large enough random tests).
Yes. The reading of polygraphs is very subjective and it's been found that they reflect only whether the person administering the test thinks the subject is guilty.
Of course whether a polygraph can frighten an innocent person enough to falsely confess is another matter, but if the subject is guilty and understands how polygraphs (don't) work, they can deceive the person administering the test very easily. There is no shortage of spies that have passed polygraphs regularly and reliably with flying colors.
Are "clearers" from Scientology any 'better' at reading a polygraph than non-"clearers"
https://www.sciencedirect.com/science/article/pii/S016926070...
>The rates of correct detection in guilty and innocent subjects were 86%, which was better than other previously used methods.
Eh, that sounds close enough to 'beyond a reasonable doubt', right?
https://www.scientificamerican.com/article/do-the-eyes-have-...
Only if you "pass". Fail one and admissible or not, it'll be brought up.
https://www.hg.org/legal-articles/is-a-polygraph-test-admiss...
That's not how it works, and even a public defender working 20 hour days who doesn't know their defendant's name would be able to get a mistrial.
"Look, I know your guy went for a polygraph, but you've not brought it up, so I assume he didn't do well. Here's what I can offer..."
This one's my favourite:
The jurors who used a Ouija board to find a murderer guilty - https://www.abc.net.au/news/2018-05-08/ouija-board-juror-mis...
I agree with all the skepticism of particular types of evidence in this thread including witness testimony and forensic evidence (I'd also add even confessions to this list). But this rather extreme conclusion doesn't follow. Evidence can be uncertain and hard to interpret, but still lead us to truth. You just need more than one data point.
In a typical criminal trial (assuming the defendant is guilty) the prosecution generally will not hang on a single dubious piece of evidence. They will often assemble a veritable mountain, if they can, because they know that a competent defense attorney will make sure that the jury knows better than anyone the various ways in which evidence can mislead.
This is not to say that everything is rosy in the criminal justice system, and that juries always get it right. There are lots of big problems: Juries are often mysterious and unreliable. Defense attorneys often do a bad job (meaning, among other things, that the prosecution can get sometimes get away with presenting a weak case based on shoddy evidence). And, lest we forget, huge numbers of criminal prosecutions end in a guilty plea, and never go to trial in the first place (sometimes for good reasons, sometimes for bad).
But I want to push back on the extreme notion that the outcome of every trial is all about rhetoric. Sure, it plays a role and some cases are better than others. But I've never seen one that was "entirely rhetoric and fudge-factor." (I'm sure it happens, but not often enough that I've ever seen it.)
>In one case, West claimed to have matched the bite marks in a half-eaten bologna sandwich to the defendant. The jury convicted. (The conviction was overturned on appeal when defense lawyers discovered that the autopsy report recorded a partial bologna sandwich in the stomach of the victim.)
https://www.washingtonpost.com/news/the-watch/wp/2015/02/17/...
Pretty much everything in forensic science turns out to be junk science over a long enough timeline. Hair, bite marks, fire progression, all junk. There's even a few cracks in the fingerprint wall. Don't get me started on all the field test kits of various types that LEOs use.
The only things that seem to be reliable are things that don't have their roots in forensic science (e.g. using DNA to identify people) and even then you still have to depend on a crime lab (run by the people doing the prosecuting) to not be sloppy.
Oh yeah. Not just incompetence, but actual malice. Recently in Massachusetts there were two high profile state forensic drug lab scandals: One where a chemist was functionally incapacitated by taking all the drugs she should have been testing [0], and one where the chemist was falsifying positive tests (!!!!!!) [1]. More recently, the state police are known to be falsifying overtime records [2]. I can't even begin to imagine what it's like in "stereotyped as corrupt" states.
[0] https://www.cbsnews.com/news/6000-drug-cases-linked-to-rogue...
[1] https://www.cbsnews.com/news/more-than-21000-drug-conviction...
[2] https://www.masslive.com/expo/news/erry-2018/12/1fc00a248688...
Which CSI has done a wonderful job of turning into super-cops in the eyes of jurys.
For decades a rate of about 5% for hung juries was typical. In more recent years some jurisdictions have seen more than 20% of cases end in hung juries. [2] Some have seen this as evidence of a rise in jury nullification, but others have argued that it's due to the 'CSI Effect' [3] with these individuals believing that, because of shows like CSI, the standard of proof required for a conviction seems to be rising - along with a reduced weighting given to things like circumstantial evidence.
[1] - https://en.wikipedia.org/wiki/Jury_nullification
[2] - https://www.washingtonpost.com/wp-srv/national/jury080299.ht...
* Taking the samples and using several solutions to snip them at given patterns.
* Taking another solution and promoting replication of the fragments.
* Using some dye and a weight sorting channel to bin the fragments by weight.
It's pretty useful for determining things like IF it is LIKELY that individuals are related.
It's also pretty good at confirming negatives (We're sure someone is NOT related to X).
It's not that great at confirming positives. That is, the results are both subjective and ambiguous given the hashing. A "positive" result here is really more of an "OK, it's likely we should run the real and expensive check, evaluate if someone might be a suspect by other merits, etc."
I would, offhand, consider a "positive" above to be enough evidence to produce /suspicion/ and /warrants/ to locate other specific evidence to ascertain an actual guilt or innocence based on harder evidence. If an actual "sequence the whole set of samples" option enters the realm of feasible tests then it would also warrant actually doing that.
Come to think of it, I'm not sure how the Ancestry/etc novelty DNA tests work. I'd assume they've isolated a few specific markers they're looking for and the processes are optimized towards identifying those and comparing combinations for those specific traits.
Not so, it’s a fairly excellent hash, one with few collisions. Better than a fingerprint. If it looks like your DNA, it most likely is.
Source: was an electrophoresis tech (not forensic) in a previous life.
And yes, the usual genetics sites do SNP tests, which are cheaper than full sequencing but mean that they only find what they’re already looking for.
The price of full sequencing is dropping rapidly, I look forward to it being a standard part of medical practice, it will save a lot of lives and improve quality of care.
Unfortunately all too often the DNA test result is used as proof of a hypothesis, not of the mere presence of surprisingly similar DNA in a swab sample.
I didn't outright say that, though; the idea was that I would prepare you for a story of a serial killer so well concealed that her existence could only be inferred from trace DNA, but THEN there's the surprise twist - there is no serial killer, it's a trick of human incompetency. BOOM!
The twist has a much greater effect because I didn't give it away at the start, but the twist also ties back in to my original statement about human incompetency - but NOT where you may have been expecting, and subverted expectations are a key part of surprise twists - and the story is also about DNA forensics. That's the previous subject again, the reader having been led around in an interesting and surprising circle.
During the suspect identification process I failed completely; the suspect was bald and had a spider tattoo on their face. I realised that I couldn’t even remember how they looked, it shocked me quite a lot. I assume it was the adrenaline.
They're considered a valid tool for coercion.
Stupid criminals who watch too much TV think they work and some cop comes in and says he failed a lie detector test and they confess.
In that way they actually do work.
Assuming all you want is a confession but if the person actually provides evidence of their own guilt they so be it.
They generally are not considered valid evidence.
The courts can differentiate it by saying that the legislature has written implied consent laws that cover what you are deemed to have consented to when operating a motor vehicle, and that the legislature has not written implied consent laws for cell phones/etc.
Right now it's a pretty easy case for the courts, though higher courts have justified much worse with much less.
It's possible a legislature could write implied consent laws for cell phones, but I don't think they have yet. Not sure if they'd withstand court review, but I am afraid they might.
Indeed - warrantless blood tests have been found unconstitutional by SCOTUS three years ago (Birchfield v. North Dakota).
Sometimes people are _so_ drunk they refuse to provide a sample without really comprehending that this will itself directly lead to getting arrested and prosecuted but minus any opportunity to get the results thrown out for any reason since it'll just come down to "Officer, did the suspect refuse consent to the required sample?".
You couldn't do that exact workaround in the US because of the Constitution, but I'm sure a creative work around can be invented.
The "workaround" in the United States is similar. When you apply for a driver's license, you agree to submit blood/breath/urine upon demand or lose said license automatically.
"the judge wrote that fingerprints and face scans were not the same as “physical evidence” when considered in a context where those body features would be used to unlock a phone."
(Emphasis mine.)
It's the context of using those body features to unlock a phone, that makes them testimonial rather than physical evidence. Outside that context, they can still be physical evidence.
But does that mean the police can't use physical evidence to unlock your phone? I don't know if it's possible to get a fingerprint from a glass and use that to unlock a phone, but if it was, would that still be legal? What about if someone wrote their password on a note?
In the case of telephones, biometric data is being used to get access to something else.
And worse, these will provide opportunities for the state to build probable cause for a stop that otherwise might not exist.
I'm going to go with strongly disagree here.
I've be interviewed by police twice after being charged with crimes that carry potential prison sentences. The interviews are voluntary in the sense you're not required to answer any of the questions, and I could have chosen to wait in a cell for my lawyer to turn up days later ... but I volunteered to respond to each question by making a mockery of their questions and processes.
These people in authority, they are not there to help you, with their badges and their guns and their attitude problems, and I don't believe it's possible for someone to "volunteer" when such a power imbalance exists.
It's an absurd use of the word. You can't "volunteer" when the other person is carrying a gun.
"voluntary" - done, given, or acting of one's own free will. You said yourself that you could have waited, but decided not to.
Alternatively you could have just done a "no comment" interview, which - let's be honest - is what the lawyer would have advised you to do, no matter if you're guilty or not.
Also, shouldn't the act of entering someone's phone be analogous to entering someone's house? I.e., wouldn't a search warrant/court order be required?
> “The undersigned finds that a biometric feature is analogous to the 20 nonverbal, physiological responses elicited during a polygraph test, which are used to determine guilt or innocence, and are considered testimonial.”
So it's analogous to a passcode because you're divulging something stored by your body, as opposed to e.g. a metal key which is artificial.
Tangentially related, it's astounding to me that polygraphs are still considered valid evidence given how widely they've been discredited.