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...which makes an 81% false positive rate remarkably good. You've massively whittled down your list of potential subjects and made the job of humans immeasurabl

...which makes an 81% false positive rate remarkably good. You've massively whittled down your list of potential subjects and made the job of humans immeasurably easier. An 81% false positive rate would be nightmarishly awful if this system served as judge, jury and executioner, but it's incredibly useful as a means of improving the signal-to-noise ratio of surveillance data.

e40 7y ago
That would be true if wiggling out of the net of justice when you are innocent were not so expensive. There are a lot of poor people who can't afford the system you speak of.
- jdietrich 7y ago
  The world is not America. Your criminal justice system might be a Kafkaesque nightmare, but ours is mostly OK.
  - bradknowles 7y ago
    Just wait. If yours isn't already as bad as ours, then just wait.
    - jdietrich 7y ago
      I'm sure that's comforting to believe, but it just isn't true. America's criminal justice system is uniquely dysfunctional in a multitude of ways, best exemplified by your extraordinarily high incarceration rate. There is no law of nature that dictates that all criminal justice systems inexorably deteriorate into tyranny, it's just a specific and fixable set of policy failures. The iniquities of pre-trial detention and cash bail are fixable. Racially biased arrest, conviction and sentencing rates are fixable. Needlessly punitive sentences and an over-reliance on incarceration are fixable. Miscarriages of justice due to pseudoscientific forensic evidence and under-funded public defenders are fixable.
  - throw20102010 7y ago
    Both the USA and UK provide legal aid for poor people even if the procedures are different. If you cannot afford a solicitor, the government will help you pay for one, but they probably won't be the best. In both countries rich people get better legal representation than poor people. Don't make the UK out to be some paradise (legal or otherwise), it struggles with plenty of its own problems.
    - jdietrich 7y ago
      The UK doesn't have cash bail, so nobody is stuck in pre-trial detention simply because they can't afford to buy their freedom. It doesn't have elected prosecutors, judges or sheriffs. It incarcerates less than a quarter as many people per capita. It doesn't have three-strike laws and uses mandatory minimum sentences only for an extremely limited number of serious offences. The UK is far from perfect, but most of the criticisms of the American criminal justice system simply don't apply.
      - merpnderp 7y ago
        Aren’t people far more likely to be a victim of crime in the UK?
        deleted 7y ago
        [deleted]
        ska 7y ago
        It doesn't seem to be true (some silly news articles notwithstanding) but these things are surprisingly difficult to compare properly.
        jdietrich 7y ago
        It's very difficult to compare like-for-like, because we have different laws and compile crime statistics differently. The intentional homicide rate is substantially lower in the UK (1.2 vs 5.35 per 100,000), as is our rate of killings by law enforcement (0.2 vs 30.4 per 10,000,000). The UK may have slightly more property crime (12.2% vs 10% of population victimised), but it's not clear if that comparison is statistically valid. https://en.wikipedia.org/wiki/List_of_countries_by_intentional_homicide_rate https://en.wikipedia.org/wiki/List_of_countries_by_intention... https://en.wikipedia.org/wiki/List_of_killings_by_law_enforcement_officers_by_countries https://en.wikipedia.org/wiki/List_of_killings_by_law_enforc... https://www.nationmaster.com/country-info/stats/Crime/Property-crime-victims https://www.nationmaster.com/country-info/stats/Crime/Proper...
  - keiru 7y ago
    Let's agree on that just for the sake of argument. Systems change, but once settled facial recognition will not go away. You might find yourself engulfed in hell before you know it.
    - lostjohnny 7y ago
      Just like now.
  - TazeTSchnitzel 7y ago
    There were big cuts to legal aid in the UK under the Coalition.
  - hdfbdtbcdg 7y ago
    You really need to read up on changes to legal aid in the UK.
    - jdietrich 7y ago
      I'm well aware of the cuts to legal aid and have lobbied against them. It is worth noting that the changes to legal aid have primarily affected civil law, with the effects on criminal law being primarily limited to means-testing for high earners and an 8.25% reduction in overall fees paid to legal practitioners. Although it is clear that the cuts have significantly impacted family, immigration and welfare benefits cases, it is not clear that they have affected the fairness of the criminal legal system.
      - hdfbdtbcdg 7y ago
        Why should an innocent richer person have to use their life savings defending a charge of which they are innocent? (Of course the poorer person would be found guilty and sent to prison so the system is even more unfair for them.)
      - DanBC 7y ago
        They've definitely affected criminal law. The secret barrister's book describes it quite well.
        hdfbdtbcdg 7y ago
        8.25% is significant cut. I wonder if that is inflation adjusted?
- kazinator 7y ago
  But we're going into this story already knowing that 81% were deemed innocent: already wiggled out.
  - electricviolet 7y ago
    So how many additional people are actually innocent but still considered suspects?
    - techrich 7y ago
      all of them are suspects, you have just not been caught yet
    - kazinator 7y ago
      Hard to guess. This would have to be people who still look like a dead-ringer for a criminal even to a human who compares their face to a database photo, and who are not able to supply ID to prove that it's just coincidental resemblance. Police have always relied on facial recognition, just not facial recognition carried out by machines. We accept imperfect facial recognition from machines if it is faster, and leaves less work for humans to deal with.
- nerdponx 7y ago
  I wonder how this 81% false positive rate compares to the false positive rate of traditional techniques for developing lists of suspects.
  - jturpin 7y ago
    I would love to know this as well. It sounds high but we have no baseline to compare it against - for all we know it could be a massive improvement.
ckozlowski 7y ago
Thank you. This is the principle that always gets overlooked anytime I or my company sees these articles. No one should ever be suggesting that these be a sole means of identification. There should always be a human in the loop. I've yet to meet a customer who's looking at this technology as a way to make decisions. In every case it's there to help make their analysts' jobs easier, by sifting through the chaff and presenting them with the data that makes the best use of their skills. Note: I work for AWS.
jonhohle 7y ago
Except for the people who are falsely accused and may be hassled in the process. Around 15 years ago I would often schedule last minute flights while traveling for work. When I did, I almost certainly would receive an enhanced screening from TSA. I was the false positive, and when traveling on tight schedules, I was not amused at the frequency in which I was considered suspect (in contrast to the treatment from the airlines, who treated me like royalty). Of course, TSAs true positive rate is 0%.
6gvONxR4sf7o 7y ago
Sorta. Mathematically yes. Socially, I dunno. When you have a test determines you to be 21% likely to be guilty but the people judging you see "99.99% accurate test" statistical innumeracy is dangerous. The best fix is to use the useful info in the smart way, but "the smart way" means fixing education problems we're already trying and failing to fix.
SkyBelow 7y ago
Assuming 0% false negatives. I am not sure such an assumption is backed by evidence.
ska 7y ago
It doesn't really work that way. Or, at least, you need some more information. There are two big assumptions you haven't made explicit. One, that the FN rate is low. If it isn't you haven't necessarily improved your SNR at all, you're just spent resources looking in the wrong place. Two, that the cost of a FP is 0. The latter obviously isn't true, so you have to weight the positive and negative impacts across all scenarios before you can tell if this is a net win. Think of this in a different context; say I have a new cancer screening protocol, with a low FN but also a high FP rate. So everyone we mark as positive gets a follow up biopsy. You say "great, we catch x% more cancers now than the old way, good win". Until someone points out that biopsies have a y% rate of catastrophic infection resulting in death. Depending how these rates balance out, we may be killing more people that we are saving....
rhizome 7y ago
An 81% false positive rate would be nightmarishly awful if this system served as judge, jury and executioner This is a highly black-and-white way of thinking about the implications. "Heck, it's only a problem if they get executed."
- jimclegg 7y ago
  We should be careful before we unnecessarily increase the number of interactions between police and the general public. For example, roadside drug test accuracy rate is abysmal but innocent people are being put in jail because uninformed LEO either don't know or don't care baout the rate. If you can't afford to fight the false charge, your life/record/job/etc is screwed. Also, these false positives tend to have a conveniently racist default twist in our country. "59% of the Houston defendants in drug arrests involving false positives were black.", I expect the number that didn't fight the charge and were wrongfully convicted is quite high as well. https://www.nytimes.com/2016/07/10/magazine/how-a-2-roadside-drug-test-sends-innocent-people-to-jail.html https://www.nytimes.com/2016/07/10/magazine/how-a-2-roadside...
  - rhizome 7y ago
    >We should be careful before we unnecessarily increase the number of interactions between police and the general public I'd say a society is more successful the more they strive to minimize law enforcement contact.
elliekelly 7y ago
> which makes an 81% false positive rate remarkably good. Friendly reminder that our _entire_ legal system was arranged by the Founders so that innocent people wouldn’t be incarcerated even if that means some guilty people walk free. Your reasoning flips the most important feature of our criminal justice system on its head. I know most people on HN haven’t dealt with the criminal justice system but being wrongly charged and, if you’re lucky, beating the charges is an incredibly awful experience. Just being charged will follow you for the rest of your life.
- lostjohnny 7y ago
  It is incredibly good nonetheless Remember this is used by police to find suspects, not to replace the judge. It means that just looking at a picture, 2 suspects every ten are successfully recognized Compared to the system we have now, were to find who's guilty police have to go trough a list of suspects were all of them except one (or a few) is innocent, 2 every 10 is very good. We're not talking about considering people guilty until proven innocent, but helping police to investigate in the right direction. In UK almost a quarter of murder cases are still unsolved. https://www.ibtimes.co.uk/almost-quarter-all-murders-are-still-unsolved-by-uk-police-home-office-1574756 https://www.ibtimes.co.uk/almost-quarter-all-murders-are-sti...
DanBC 7y ago
If you're arrested and then a few hours later de-arrested that will have an impact on your life. It means you have to explain the arrest on any enhanced DBS you need. It means you probably longer qualify for visa free travel to the US and will need to ask the US embassy if you have to get a visa or not.
miliui 7y ago
FTS you 1984 psycho
kaonashi 7y ago
…assuming there aren't any false negatives as well

e40 7y ago

That would be true if wiggling out of the net of justice when you are innocent were not so expensive. There are a lot of poor people who can't afford the system you speak of.

jdietrich 7y ago
The world is not America. Your criminal justice system might be a Kafkaesque nightmare, but ours is mostly OK.
- bradknowles 7y ago
  Just wait. If yours isn't already as bad as ours, then just wait.
  - jdietrich 7y ago
    I'm sure that's comforting to believe, but it just isn't true. America's criminal justice system is uniquely dysfunctional in a multitude of ways, best exemplified by your extraordinarily high incarceration rate. There is no law of nature that dictates that all criminal justice systems inexorably deteriorate into tyranny, it's just a specific and fixable set of policy failures. The iniquities of pre-trial detention and cash bail are fixable. Racially biased arrest, conviction and sentencing rates are fixable. Needlessly punitive sentences and an over-reliance on incarceration are fixable. Miscarriages of justice due to pseudoscientific forensic evidence and under-funded public defenders are fixable.
- throw20102010 7y ago
  Both the USA and UK provide legal aid for poor people even if the procedures are different. If you cannot afford a solicitor, the government will help you pay for one, but they probably won't be the best. In both countries rich people get better legal representation than poor people. Don't make the UK out to be some paradise (legal or otherwise), it struggles with plenty of its own problems.
  - jdietrich 7y ago
    The UK doesn't have cash bail, so nobody is stuck in pre-trial detention simply because they can't afford to buy their freedom. It doesn't have elected prosecutors, judges or sheriffs. It incarcerates less than a quarter as many people per capita. It doesn't have three-strike laws and uses mandatory minimum sentences only for an extremely limited number of serious offences. The UK is far from perfect, but most of the criticisms of the American criminal justice system simply don't apply.
    - merpnderp 7y ago
      Aren’t people far more likely to be a victim of crime in the UK?
      - deleted 7y ago
        [deleted]
      - ska 7y ago
        It doesn't seem to be true (some silly news articles notwithstanding) but these things are surprisingly difficult to compare properly.
      - jdietrich 7y ago
        It's very difficult to compare like-for-like, because we have different laws and compile crime statistics differently. The intentional homicide rate is substantially lower in the UK (1.2 vs 5.35 per 100,000), as is our rate of killings by law enforcement (0.2 vs 30.4 per 10,000,000). The UK may have slightly more property crime (12.2% vs 10% of population victimised), but it's not clear if that comparison is statistically valid. https://en.wikipedia.org/wiki/List_of_countries_by_intentional_homicide_rate https://en.wikipedia.org/wiki/List_of_countries_by_intention... https://en.wikipedia.org/wiki/List_of_killings_by_law_enforcement_officers_by_countries https://en.wikipedia.org/wiki/List_of_killings_by_law_enforc... https://www.nationmaster.com/country-info/stats/Crime/Property-crime-victims https://www.nationmaster.com/country-info/stats/Crime/Proper...
- keiru 7y ago
  Let's agree on that just for the sake of argument. Systems change, but once settled facial recognition will not go away. You might find yourself engulfed in hell before you know it.
  - lostjohnny 7y ago
    Just like now.
- TazeTSchnitzel 7y ago
  There were big cuts to legal aid in the UK under the Coalition.
- hdfbdtbcdg 7y ago
  You really need to read up on changes to legal aid in the UK.
  - jdietrich 7y ago
    I'm well aware of the cuts to legal aid and have lobbied against them. It is worth noting that the changes to legal aid have primarily affected civil law, with the effects on criminal law being primarily limited to means-testing for high earners and an 8.25% reduction in overall fees paid to legal practitioners. Although it is clear that the cuts have significantly impacted family, immigration and welfare benefits cases, it is not clear that they have affected the fairness of the criminal legal system.
    - hdfbdtbcdg 7y ago
      Why should an innocent richer person have to use their life savings defending a charge of which they are innocent? (Of course the poorer person would be found guilty and sent to prison so the system is even more unfair for them.)
    - DanBC 7y ago
      They've definitely affected criminal law. The secret barrister's book describes it quite well.
      - hdfbdtbcdg 7y ago
        8.25% is significant cut. I wonder if that is inflation adjusted?
kazinator 7y ago
But we're going into this story already knowing that 81% were deemed innocent: already wiggled out.
- electricviolet 7y ago
  So how many additional people are actually innocent but still considered suspects?
  - techrich 7y ago
    all of them are suspects, you have just not been caught yet
  - kazinator 7y ago
    Hard to guess. This would have to be people who still look like a dead-ringer for a criminal even to a human who compares their face to a database photo, and who are not able to supply ID to prove that it's just coincidental resemblance. Police have always relied on facial recognition, just not facial recognition carried out by machines. We accept imperfect facial recognition from machines if it is faster, and leaves less work for humans to deal with.
nerdponx 7y ago
I wonder how this 81% false positive rate compares to the false positive rate of traditional techniques for developing lists of suspects.
- jturpin 7y ago
  I would love to know this as well. It sounds high but we have no baseline to compare it against - for all we know it could be a massive improvement.

ckozlowski 7y ago

Thank you. This is the principle that always gets overlooked anytime I or my company sees these articles. No one should ever be suggesting that these be a sole means of identification. There should always be a human in the loop. I've yet to meet a customer who's looking at this technology as a way to make decisions. In every case it's there to help make their analysts' jobs easier, by sifting through the chaff and presenting them with the data that makes the best use of their skills. Note: I work for AWS.

jonhohle 7y ago

Except for the people who are falsely accused and may be hassled in the process. Around 15 years ago I would often schedule last minute flights while traveling for work. When I did, I almost certainly would receive an enhanced screening from TSA. I was the false positive, and when traveling on tight schedules, I was not amused at the frequency in which I was considered suspect (in contrast to the treatment from the airlines, who treated me like royalty). Of course, TSAs true positive rate is 0%.

6gvONxR4sf7o 7y ago

Sorta. Mathematically yes. Socially, I dunno. When you have a test determines you to be 21% likely to be guilty but the people judging you see "99.99% accurate test" statistical innumeracy is dangerous. The best fix is to use the useful info in the smart way, but "the smart way" means fixing education problems we're already trying and failing to fix.

SkyBelow 7y ago

Assuming 0% false negatives. I am not sure such an assumption is backed by evidence.

ska 7y ago

It doesn't really work that way. Or, at least, you need some more information. There are two big assumptions you haven't made explicit. One, that the FN rate is low. If it isn't you haven't necessarily improved your SNR at all, you're just spent resources looking in the wrong place. Two, that the cost of a FP is 0. The latter obviously isn't true, so you have to weight the positive and negative impacts across all scenarios before you can tell if this is a net win. Think of this in a different context; say I have a new cancer screening protocol, with a low FN but also a high FP rate. So everyone we mark as positive gets a follow up biopsy. You say "great, we catch x% more cancers now than the old way, good win". Until someone points out that biopsies have a y% rate of catastrophic infection resulting in death. Depending how these rates balance out, we may be killing more people that we are saving....

rhizome 7y ago

An 81% false positive rate would be nightmarishly awful if this system served as judge, jury and executioner This is a highly black-and-white way of thinking about the implications. "Heck, it's only a problem if they get executed."

jimclegg 7y ago
We should be careful before we unnecessarily increase the number of interactions between police and the general public. For example, roadside drug test accuracy rate is abysmal but innocent people are being put in jail because uninformed LEO either don't know or don't care baout the rate. If you can't afford to fight the false charge, your life/record/job/etc is screwed. Also, these false positives tend to have a conveniently racist default twist in our country. "59% of the Houston defendants in drug arrests involving false positives were black.", I expect the number that didn't fight the charge and were wrongfully convicted is quite high as well. https://www.nytimes.com/2016/07/10/magazine/how-a-2-roadside-drug-test-sends-innocent-people-to-jail.html https://www.nytimes.com/2016/07/10/magazine/how-a-2-roadside...
- rhizome 7y ago
  >We should be careful before we unnecessarily increase the number of interactions between police and the general public I'd say a society is more successful the more they strive to minimize law enforcement contact.

elliekelly 7y ago

> which makes an 81% false positive rate remarkably good. Friendly reminder that our _entire_ legal system was arranged by the Founders so that innocent people wouldn’t be incarcerated even if that means some guilty people walk free. Your reasoning flips the most important feature of our criminal justice system on its head. I know most people on HN haven’t dealt with the criminal justice system but being wrongly charged and, if you’re lucky, beating the charges is an incredibly awful experience. Just being charged will follow you for the rest of your life.

lostjohnny 7y ago
It is incredibly good nonetheless Remember this is used by police to find suspects, not to replace the judge. It means that just looking at a picture, 2 suspects every ten are successfully recognized Compared to the system we have now, were to find who's guilty police have to go trough a list of suspects were all of them except one (or a few) is innocent, 2 every 10 is very good. We're not talking about considering people guilty until proven innocent, but helping police to investigate in the right direction. In UK almost a quarter of murder cases are still unsolved. https://www.ibtimes.co.uk/almost-quarter-all-murders-are-still-unsolved-by-uk-police-home-office-1574756 https://www.ibtimes.co.uk/almost-quarter-all-murders-are-sti...

DanBC 7y ago

If you're arrested and then a few hours later de-arrested that will have an impact on your life. It means you have to explain the arrest on any enhanced DBS you need. It means you probably longer qualify for visa free travel to the US and will need to ask the US embassy if you have to get a visa or not.

miliui 7y ago

FTS you 1984 psycho

kaonashi 7y ago

…assuming there aren't any false negatives as well