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The Case Against DNA
Hugh Pickens writes "Thanks to fast-paced television crime shows such as CSI, we have come to regard DNA evidence as incontestable. But BBC reports that David Butler has every right to be cynical about the use of DNA evidence by the police. Butler spent eight months in prison, on remand, facing murder charges after his DNA was allegedly found on the victim. 'I think in the current climate [DNA] has made police lazy,' says Butler. 'It doesn't matter how many times someone like me writes to them, imploring they look at the evidence... they put every hope they had in the DNA result.' The police had accused Butler of murdering a woman, Anne Marie Foy, in 2005 — his DNA sample was on record after he had willingly given it to them as part of an investigation into a burglary at his mother's home some years earlier. But Butler has a rare skin condition, which means he sheds flakes of skin, leaving behind much larger traces of DNA than the average person. Butler worked as a taxi driver, and so it was possible for his DNA to be transferred from his taxi via money or another person, onto the murder victim. The case eventually went to trial and Butler was acquitted after CCTV evidence allegedly placing Butler in the area where the murder took place was disproved. Professor Allan Jamieson, head of the Glasgow-based Forensic Institute, has become a familiar thorn in the side of prosecutors seeking to rely on DNA evidence and has appeared as an expert witness for the defense in several important DNA-centered trials, most notably that of Sean Hoey, who was cleared of carrying out the 1998 Omagh bombing, which killed 29 people. Jamieson's main concern about the growing use of DNA in court cases is that a number of important factors — human error, contamination, simple accident — can suggest guilt where there is none. 'Does anyone realize how easy it is to leave a couple of cells of your DNA somewhere?' says Jamieson. 'You could shake my hand and I could put that hand down hundreds of miles away and leave your cells behind. In many cases, the question is not "Is it my DNA?", but 'How did it get there?"'"
this is england but here in the US you need beyond a reasonable doubt. the cops can check the phone for prints and there is a record of movement by tracking every tower it hits. combine with CCTV evidence of stores and other cameras along with credit card transactions it should be fairly easy to show where you were
i've been on a criminal case jury and we ruled not guilty in a half hour because the cops had a weak case
Here. He surgically implanted a vial of someone else's blood into his arm prior to taking the DNA test. He manipulated the collector to take it from his arm rather than the standard finger prick.
British shows don't travel across the Atlantic so well, so their comedy often has to be translated into an American version where the jokes are spelled out more explicitly to fit with American humour.
You sound like an American tv producer, not an American. Me and most of my friends prefer Britcoms to Sitcoms; example, the Office. British version far superior in every way. So stick your "American humour" up you know where.
Python: 'And then suddenly you have a language which says "we're all stuck with whatever the whiniest coder wants".'
Not really. The perfect DNA test returns a result of a comparison between Sample A, and Sample B. The results are either 'MATCH, NO MATCH, or inconclusive'.
The problem is that people are basically adding meta-data to the Yes/No/error results. A confirmation a match is nothing more than a confirmation of a match, it doesn't tell you a single thing more than that. It doesn't even tell you that the person producing that DNA was there. Additional evidence is necessary in order to draw that conclusion.
However, this is NOT a problem with the traditional exculpatory DNA evidence. The casting of doubt is on the meta-results of the DNA, not the match/mismatch itself.
Thus, with exculpatory DNA evidence, the defence isn't trying to prove that the Defendant was in any particular location, all they are trying to prove is that DNA sample A does/doesn't match DNA sample B.
If you have a DNA sample from a crime scene, and I'm trying to show that such a sample does not match my client, it doesn't matter if my client was in the room, out of the room, or 3,000 miles away. If the DNA doesn't match, then the DNA doesn't match. I'm not trying to prove anything more than that.
It is the prosecution that is trying to add that extra data to the DNA, not the defense. The prosecutor has to first show that the DNA matches, THEN the prosecutor must also present evidence that the DNA could only be where it was because the defendant put it there.
Again, the DNA becomes a non-issue (for the purposes of identifying the defendent) for the defence the instant it doesn't match the defendent (in general)
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
That's the US though, the UK has a different statement of fact: "it may harm your defence if you fail to mention when questioned something you later rely on in court"
Yes, believe it or not, fingerprints are far more reliable than DNA.
Except that no one has actually done the population level research needed in order to prove that fingerprints are unique, and two different finger print analysts are very likely to come up with different analyses of the same print.
There has not been a known case of two people having the same fingerprint
Which is irrelevant if different fingerprint analysts cannot reliably score the same fingerprints the same way.
Give me Classic Slashdot or give me death!
The "reasonable doubt" standard of proof applies only to the prosecution. The defence does not have to prove anything, either beyond reasonable doubt or to any standard of proof whatsoever. They merely have to raise enough evidence to prevent the prosecution from proving their case beyond reasonable doubt.
That being the case it's meaningless to talk about whether there is reasonable doubt as to whether the phone was in the owner's possession. That is simply never a relevant question. The question is whether, taking the case in its totality, the evidence is such that a jury could be satisfied beyond reasonable doubt that the defendant is guilty. If the evidence amounted to an inconclusive DNA match and phone records that did not place his phone at the place of the murder then the evidence would certainly not be sufficient. That is the case notwithstanding that none of the evidence is directly exculpatory.
(I'm not saying that that was the totality of the evidence in this case; in fact, given that he was denied bail for 8 months, I suspect that there was both more evidence and some history of criminality. That is simply speculation however.)