5 ms·

A new technique to work out a corpse's time of death

25 points by lxm 3y ago

rwmj 3y ago
Training an AI. This will be interesting the first time a suspect tries to challenge the forensics in court.
- 8organicbits 3y ago
  I think Daubert is the relevant rule. Knowing the error rate and being subject to peer review should be helpful here. https://en.m.wikipedia.org/wiki/Daubert_standard https://en.m.wikipedia.org/wiki/Daubert_standard
reportgunner 3y ago
The new technique is AI, that's the whole article.
- wizzwizz4 3y ago
  It doesn't even say whether it's an expert system (reasonable) or machine learning (unreasonable).
mhb 3y ago
Down on the Body Farm: Unlocking the Forensic Secrets of Decaying Corpses https://undark.org/2019/11/11/how-microbes-could-aid-forensic-detectives/ https://undark.org/2019/11/11/how-microbes-could-aid-forensi...
- pimlottc 3y ago
  Is this the same technique discussed in the submission or just a related article?
helsinkiandrew 3y ago
https://archive.ph/PpQlh https://archive.ph/PpQlh
deleted 3y ago
[deleted]
nisegami 3y ago
Considering the low bar for what gets allowed as forensic evidence, I think they'd have to try really hard to make things worse.
wolverine876 3y ago
Based only on the OP: It seems like a 'trust the magic computer' scenario, a prime example of the misuse of AI and its great risks: If it the output is wrong, innocent people go to jail, the guilty go free, and families are confused with misinformation about their loved one's death. There is no discussion of the system's accuracy or an attempt to determine it empirically (possibly an omission by the article and not the developers). It does say, > At present the model offers a range of days within which it is 80% confident the true pmi lies ... Taken literally, that is the AI stating the AI's accuracy instead of an empirical test against known real-world outcomes. And look at the training data: > About 1,800 of these are real-world cases involving the discovery of a body. The rest are drawn from forensic experiments at so-called “body farms” in Texas and Tennessee, in which corpses are left to decay for weeks and months under varied circumstances. Yet elsewhere they say that real-world cases are highly unreliable: > Working out when a person has died is the most basic (but frustratingly imprecise) part of a forensic investigator’s work. For decades these specialists have had to rely on intuition, combined with observations of the state of the deceased and clues such as temperature, both of the dead body and the environment. Different bodies decay at different rates, however, and individual circumstances can throw off the most careful pmi calculations. A body found in a ditch in northern England in 2004, for example, was given an erroneously late time of death because the ditch was shielded from sunlight and the colder-than-expected conditions had helped preserve the corpse. / Forensic-science journals are full of such cases ... It would seem that you are training the computer to make the same errors with the same biases that the foresnic investigators already make - unless they have some objective source for the actual time of death in those real-world cases. Hopefully, it's just a limitation of the article, not of the actual software.
krunck 3y ago
I thought forensic entomology in combination with other tools was quite accurate. I wonder how it compares to this AI model.
tyingq 3y ago
Should be interesting if someone ends up convicted partially based on timelines covered, and not covered, by an alibi...based on the AI's idea of time of death.
beryilma 3y ago
If we need to go the AI route, isn't the timestamp of someone's last TicToc/X/Instagram post a better indicator of time of death?
- reaperman 3y ago
  No. And this doesn't add anything constructive to the discussion. Please review the HN commenting guidelines (link is at the bottom of this page).
- mhuffman 3y ago
  I think you are right and I don't know why this other person attacked your comment this way. People in fact do use last online activity to build a timeline for crimes right now. Whereas, this AI nonsense will be eviscerated the first time it is ever used against someone with a good attorney.
gustavus 3y ago
Relevant XKCD https://xkcd.com/1968/ https://xkcd.com/1968/ Glad to see were going to start letting the justice system become dependent on black box stochastic parrots. After all the government + technology is always right and incorruptible it's not like horrible things like hundreds of innocent government employees being imprisoned and prosecuted over errors in software ever happens, right? right?
- luma 3y ago
  It'd be hard to make it worse than modern forensic "science", which is almost never falsifiable and always executed by someone being paid by an organization with an interest in a particular outcome.
deleted 3y ago
[deleted]
neuronexmachina 3y ago
After a bit of searching, I think this is the relevant paper for the database+technique: https://www.sciencedirect.com/science/article/pii/S037907382400015X https://www.sciencedirect.com/science/article/pii/S037907382... > geoFOR: A collaborative forensic taphonomy database for estimating the postmortem interval https://www.geoforapp.info/machine-learning-model https://www.geoforapp.info/machine-learning-model

25 points by lxm 3y ago

rwmj 3y ago

Training an AI. This will be interesting the first time a suspect tries to challenge the forensics in court.

8organicbits 3y ago
I think Daubert is the relevant rule. Knowing the error rate and being subject to peer review should be helpful here. https://en.m.wikipedia.org/wiki/Daubert_standard https://en.m.wikipedia.org/wiki/Daubert_standard

reportgunner 3y ago

The new technique is AI, that's the whole article.

wizzwizz4 3y ago
It doesn't even say whether it's an expert system (reasonable) or machine learning (unreasonable).

mhb 3y ago

Down on the Body Farm: Unlocking the Forensic Secrets of Decaying Corpses https://undark.org/2019/11/11/how-microbes-could-aid-forensic-detectives/ https://undark.org/2019/11/11/how-microbes-could-aid-forensi...

pimlottc 3y ago
Is this the same technique discussed in the submission or just a related article?

helsinkiandrew 3y ago

https://archive.ph/PpQlh https://archive.ph/PpQlh

deleted 3y ago

[deleted]

nisegami 3y ago

Considering the low bar for what gets allowed as forensic evidence, I think they'd have to try really hard to make things worse.

wolverine876 3y ago

Based only on the OP: It seems like a 'trust the magic computer' scenario, a prime example of the misuse of AI and its great risks: If it the output is wrong, innocent people go to jail, the guilty go free, and families are confused with misinformation about their loved one's death. There is no discussion of the system's accuracy or an attempt to determine it empirically (possibly an omission by the article and not the developers). It does say, > At present the model offers a range of days within which it is 80% confident the true pmi lies ... Taken literally, that is the AI stating the AI's accuracy instead of an empirical test against known real-world outcomes. And look at the training data: > About 1,800 of these are real-world cases involving the discovery of a body. The rest are drawn from forensic experiments at so-called “body farms” in Texas and Tennessee, in which corpses are left to decay for weeks and months under varied circumstances. Yet elsewhere they say that real-world cases are highly unreliable: > Working out when a person has died is the most basic (but frustratingly imprecise) part of a forensic investigator’s work. For decades these specialists have had to rely on intuition, combined with observations of the state of the deceased and clues such as temperature, both of the dead body and the environment. Different bodies decay at different rates, however, and individual circumstances can throw off the most careful pmi calculations. A body found in a ditch in northern England in 2004, for example, was given an erroneously late time of death because the ditch was shielded from sunlight and the colder-than-expected conditions had helped preserve the corpse. / Forensic-science journals are full of such cases ... It would seem that you are training the computer to make the same errors with the same biases that the foresnic investigators already make - unless they have some objective source for the actual time of death in those real-world cases. Hopefully, it's just a limitation of the article, not of the actual software.

krunck 3y ago

I thought forensic entomology in combination with other tools was quite accurate. I wonder how it compares to this AI model.

tyingq 3y ago

Should be interesting if someone ends up convicted partially based on timelines covered, and not covered, by an alibi...based on the AI's idea of time of death.

beryilma 3y ago

If we need to go the AI route, isn't the timestamp of someone's last TicToc/X/Instagram post a better indicator of time of death?

reaperman 3y ago
No. And this doesn't add anything constructive to the discussion. Please review the HN commenting guidelines (link is at the bottom of this page).
mhuffman 3y ago
I think you are right and I don't know why this other person attacked your comment this way. People in fact do use last online activity to build a timeline for crimes right now. Whereas, this AI nonsense will be eviscerated the first time it is ever used against someone with a good attorney.

gustavus 3y ago

Relevant XKCD https://xkcd.com/1968/ https://xkcd.com/1968/ Glad to see were going to start letting the justice system become dependent on black box stochastic parrots. After all the government + technology is always right and incorruptible it's not like horrible things like hundreds of innocent government employees being imprisoned and prosecuted over errors in software ever happens, right? right?

luma 3y ago
It'd be hard to make it worse than modern forensic "science", which is almost never falsifiable and always executed by someone being paid by an organization with an interest in a particular outcome.

deleted 3y ago

[deleted]

neuronexmachina 3y ago

After a bit of searching, I think this is the relevant paper for the database+technique: https://www.sciencedirect.com/science/article/pii/S037907382400015X https://www.sciencedirect.com/science/article/pii/S037907382... > geoFOR: A collaborative forensic taphonomy database for estimating the postmortem interval https://www.geoforapp.info/machine-learning-model https://www.geoforapp.info/machine-learning-model