4 ms·

Just like the inmate in Texas executed, and (wrongfully?) convicted on pseudo-science arson investigation evidence. I wonder what other type of crap is putting

Just like the inmate in Texas executed, and (wrongfully?) convicted on pseudo-science arson investigation evidence. I wonder what other type of crap is putting innocent people in jail? Maybe more interesting question: how can a jury of average citizens be expected to weigh this evidence when even FBI task forces can't completely figure it out?

A_COMPUTER 12y ago
>I wonder what other type of crap is putting innocent people in jail? Rhetorical question? It's polygraph, drug sniffing dogs and breathalyzer. There was a court case a while back about drug sniffing dogs that presented the empirically demonstrated fact that the dogs present false positives all the time; but the judges concluded that it resulted in so many convictions that it would be a disaster to prevent their being evidence in court (analogous to witch dunkings, I suppose.) And breathalyzers are electronic devices whose source code is not auditable because the it is a "trade secret." Convicted by breathalyzer result? Can't challenge the black box's findings.
- dobbsbob 12y ago
  Police also use questionable blood splatter pattern 'science' they draw sweeping conclusions from
- stephen_g 12y ago
  Do they convict based on a breathalyser reading alone in the US? I'm fairly sure that in my country/state, the breathalyser can only provide probable cause for them to do a blood test. Also, how could sniffer dogs provide evidence for court? Surely they couldn't convict without actually finding drugs?
  - judk 12y ago
    Dogs are used to (fraudulently) excuse otherwise-illegal searches, but otherwise evidence is same as otherwise.
kevinpet 12y ago
Other crap? Probably DNA. If you suspect someone for various reasons, and then get a DNA match, it's almost certain that you have the right person. If, on the other hand, you have a DNA profile, and you search the 10,000,000 entry FBI CODIS database, there's somewhere between a 1 in 10k to 1 in 3m chance that you'll get a hit on someone other than the person who left the sample. This seems to be rather understudied. Prosecutors like to talk about the probability that two people chosen at random would match. But that's not the correct value when you use DNA to locate the suspect. One thing that would be useful would be for the FBI to report on collisions and near-collisions between known profiles added to the database.

A_COMPUTER 12y ago

>I wonder what other type of crap is putting innocent people in jail? Rhetorical question? It's polygraph, drug sniffing dogs and breathalyzer. There was a court case a while back about drug sniffing dogs that presented the empirically demonstrated fact that the dogs present false positives all the time; but the judges concluded that it resulted in so many convictions that it would be a disaster to prevent their being evidence in court (analogous to witch dunkings, I suppose.) And breathalyzers are electronic devices whose source code is not auditable because the it is a "trade secret." Convicted by breathalyzer result? Can't challenge the black box's findings.

dobbsbob 12y ago
Police also use questionable blood splatter pattern 'science' they draw sweeping conclusions from
stephen_g 12y ago
Do they convict based on a breathalyser reading alone in the US? I'm fairly sure that in my country/state, the breathalyser can only provide probable cause for them to do a blood test. Also, how could sniffer dogs provide evidence for court? Surely they couldn't convict without actually finding drugs?
- judk 12y ago
  Dogs are used to (fraudulently) excuse otherwise-illegal searches, but otherwise evidence is same as otherwise.

kevinpet 12y ago

Other crap? Probably DNA. If you suspect someone for various reasons, and then get a DNA match, it's almost certain that you have the right person. If, on the other hand, you have a DNA profile, and you search the 10,000,000 entry FBI CODIS database, there's somewhere between a 1 in 10k to 1 in 3m chance that you'll get a hit on someone other than the person who left the sample. This seems to be rather understudied. Prosecutors like to talk about the probability that two people chosen at random would match. But that's not the correct value when you use DNA to locate the suspect. One thing that would be useful would be for the FBI to report on collisions and near-collisions between known profiles added to the database.