4 ms·

I was on a jury for a murder trial, and so I have some insight into how juries work. At one point, when I was splitting some hairs and discussing the meaning o

I was on a jury for a murder trial, and so I have some insight into how juries work. At one point, when I was splitting some hairs and discussing the meaning of some small details from the evidence, one of the other jurors got impatient and reached for the coroner's photo of the victim. "Someone died here, you realize."

clicks 13y ago
You should have taken him to a side and told him to go watch 12 Angry Men when he gets home.
- GeneralMayhem 13y ago
  Or smacked him and told him to grow the fuck up.
- Symmetry 13y ago
  12 Angry Men might, perhaps, not be the best example. http://rationallyspeaking.blogspot.com/2012/11/odds-again-bayes-made-usable.html http://rationallyspeaking.blogspot.com/2012/11/odds-again-ba... EDIT: Actually, this is the one I should have linked to: http://www.avclub.com/articles/did-12-angry-men-get-it-wrong,83245/ http://www.avclub.com/articles/did-12-angry-men-get-it-wrong...
  - digipaper 13y ago
    That doesn't dispute anything about 12 Angry Men for me.
  - gohrt 13y ago
    The AV club article assumes that people never lie or are unreliable witnesses, even though the movie presents clear evidence to the contrary (and this is well known in the real world), assumes that the police conduct a thorough investigation instead of railroading a suspect who fits their prejudicial profile, and assumes things (like the knife) are uncommon because they are foreign to himself, though they may be quite popular in other social circles. That's exactly the point of the movie, and the author completely missed it.
  - AnthonyMouse 13y ago
    The avclub link makes more errors than I can count, honestly. For one, you don't combine the probabilities unless they're independent. So for example, the kid losing his knife and the murder being committed by the same kind of knife aren't independent, because it's plausible that the kid left the knife at his father's place and the actual killer used it to commit the murder. The next problem is that prosecutors systematically reinforce confirmation bias in presenting their case. The probability that someone has brown eyes and is 5'7" tall and lives in New York and knows the victim and has a motive etc. etc. would seem to be strong evidence (especially if you're assuming them all to be independent, which they're not), but that only works if you're taking an unbiased sample of the possible characteristics of the perpetrator, which the prosecutor explicitly does the opposite of. If there is no apparent motive, or the knife used to kill the victim isn't a match for the one the defendant is known to have, or the perpetrator was wearing a suit and the defendant isn't known to own a suit, you won't hear any of that from the prosecution. And if you only consider the things that match, using the article's flawed method, all additional evidence can only ever increase the probability of guilt, since any evidence to the contrary doesn't make it into the calculation. All you have to do is keep collecting evidence and excluding anything that doesn't comport with the prosecution's theory of the crime and soon you have a seemingly insurmountable case. Then you have the "DNA database" problem with statistics. Take a 1 in 10,000 chance and it sounds like solid proof ("99.99%") but if the population you're testing against is 6,000,000,000 people then you still have a pool of suspects containing 600,000 people. You can't then just pick one of those people arbitrarily and claim a 99.99% chance that that was the perpetrator, the probability that a person is the actual perpetrator if chosen at random from the group of individuals whose DNA would match is only ~0.000167%. It isn't good enough to prove that a defendant is statistically in the top thousand people in the city as far as probability to have been the perpetrator of a particular crime. You still have to exclude all the others or you'll convict the wrong man.
brazzy 13y ago
Appropriate response: "If we convict the wrong guy, the real murderer goes free, you realize".
- impendia 13y ago
  Actually, it turns out that that wasn't true, at least not under the relevant law. The defendant was a gang member and a participant in an armed robbery, and when things got ugly (the victims fought back) one of the gang members shot one of the victims. It was not proved to us that the defendant was the shooter, but -- as I was shocked to learn -- California law put him on the hook for the murder. Possibly whoever actually shot the victim is still at large. The shooting took place at night, outdoors, the eyewitnesses were all drunk, and their testimony made it clear that, under the circumstances, they could barely tell one black man from another.
  - bradleyjg 13y ago
    It's called felony murder. If someone is killed during the commission of: robbery, rape, arson, burglary, or while escaping from prison, anyone involved in the underlying crime is liable for the death.
dragonwriter 13y ago
I was on a jury for an arson trial, and the deliberations were pleasant and rational and focussed on the evidence and what it meant without anything like that. Some of its probably the difference between murder and arson without personal injury in the mix, some of it is probably the luck of the draw in the jury pool. How a jury worked and how juries work aren't really the same thing.
- impendia 13y ago
  I should add: The majority of what I experienced was similar to what you did.
tehwalrus 13y ago
I was on a jury (robbery) in the UK. It's a crime to say, afterwards, what happened in a jury room in the UK.
- deleted 13y ago
  [deleted]
  - tehwalrus 13y ago
    [REDACTED].
- tomjen3 13y ago
  So could you punch one of the other Juriors and get away with it, since they can't press charges?
  - tehwalrus 13y ago
    ahh, it may only be "deliberations" that are protected. so you'd probably be able to say "he punched me!" but not why...
Fomite 13y ago
Weirdly, a jury I was on absolutely went for me arguing something was "Necessary, but not sufficient" during our deliberation. That one surprised me.

clicks 13y ago

You should have taken him to a side and told him to go watch 12 Angry Men when he gets home.

GeneralMayhem 13y ago
Or smacked him and told him to grow the fuck up.
Symmetry 13y ago
12 Angry Men might, perhaps, not be the best example. http://rationallyspeaking.blogspot.com/2012/11/odds-again-bayes-made-usable.html http://rationallyspeaking.blogspot.com/2012/11/odds-again-ba... EDIT: Actually, this is the one I should have linked to: http://www.avclub.com/articles/did-12-angry-men-get-it-wrong,83245/ http://www.avclub.com/articles/did-12-angry-men-get-it-wrong...
- digipaper 13y ago
  That doesn't dispute anything about 12 Angry Men for me.
- gohrt 13y ago
  The AV club article assumes that people never lie or are unreliable witnesses, even though the movie presents clear evidence to the contrary (and this is well known in the real world), assumes that the police conduct a thorough investigation instead of railroading a suspect who fits their prejudicial profile, and assumes things (like the knife) are uncommon because they are foreign to himself, though they may be quite popular in other social circles. That's exactly the point of the movie, and the author completely missed it.
- AnthonyMouse 13y ago
  The avclub link makes more errors than I can count, honestly. For one, you don't combine the probabilities unless they're independent. So for example, the kid losing his knife and the murder being committed by the same kind of knife aren't independent, because it's plausible that the kid left the knife at his father's place and the actual killer used it to commit the murder. The next problem is that prosecutors systematically reinforce confirmation bias in presenting their case. The probability that someone has brown eyes and is 5'7" tall and lives in New York and knows the victim and has a motive etc. etc. would seem to be strong evidence (especially if you're assuming them all to be independent, which they're not), but that only works if you're taking an unbiased sample of the possible characteristics of the perpetrator, which the prosecutor explicitly does the opposite of. If there is no apparent motive, or the knife used to kill the victim isn't a match for the one the defendant is known to have, or the perpetrator was wearing a suit and the defendant isn't known to own a suit, you won't hear any of that from the prosecution. And if you only consider the things that match, using the article's flawed method, all additional evidence can only ever increase the probability of guilt, since any evidence to the contrary doesn't make it into the calculation. All you have to do is keep collecting evidence and excluding anything that doesn't comport with the prosecution's theory of the crime and soon you have a seemingly insurmountable case. Then you have the "DNA database" problem with statistics. Take a 1 in 10,000 chance and it sounds like solid proof ("99.99%") but if the population you're testing against is 6,000,000,000 people then you still have a pool of suspects containing 600,000 people. You can't then just pick one of those people arbitrarily and claim a 99.99% chance that that was the perpetrator, the probability that a person is the actual perpetrator if chosen at random from the group of individuals whose DNA would match is only ~0.000167%. It isn't good enough to prove that a defendant is statistically in the top thousand people in the city as far as probability to have been the perpetrator of a particular crime. You still have to exclude all the others or you'll convict the wrong man.

brazzy 13y ago

Appropriate response: "If we convict the wrong guy, the real murderer goes free, you realize".

impendia 13y ago
Actually, it turns out that that wasn't true, at least not under the relevant law. The defendant was a gang member and a participant in an armed robbery, and when things got ugly (the victims fought back) one of the gang members shot one of the victims. It was not proved to us that the defendant was the shooter, but -- as I was shocked to learn -- California law put him on the hook for the murder. Possibly whoever actually shot the victim is still at large. The shooting took place at night, outdoors, the eyewitnesses were all drunk, and their testimony made it clear that, under the circumstances, they could barely tell one black man from another.
- bradleyjg 13y ago
  It's called felony murder. If someone is killed during the commission of: robbery, rape, arson, burglary, or while escaping from prison, anyone involved in the underlying crime is liable for the death.

dragonwriter 13y ago

I was on a jury for an arson trial, and the deliberations were pleasant and rational and focussed on the evidence and what it meant without anything like that. Some of its probably the difference between murder and arson without personal injury in the mix, some of it is probably the luck of the draw in the jury pool. How a jury worked and how juries work aren't really the same thing.

impendia 13y ago
I should add: The majority of what I experienced was similar to what you did.

tehwalrus 13y ago

I was on a jury (robbery) in the UK. It's a crime to say, afterwards, what happened in a jury room in the UK.

deleted 13y ago
[deleted]
- tehwalrus 13y ago
  [REDACTED].
tomjen3 13y ago
So could you punch one of the other Juriors and get away with it, since they can't press charges?
- tehwalrus 13y ago
  ahh, it may only be "deliberations" that are protected. so you'd probably be able to say "he punched me!" but not why...

Fomite 13y ago

Weirdly, a jury I was on absolutely went for me arguing something was "Necessary, but not sufficient" during our deliberation. That one surprised me.