Polygraphs are not even 50% accurate. Totally unreliable, hence why they're inadmissible in court.
DNA tests -- well it depends what they test. The 10 loci test is not enough, and it could fit multiple people and convict the wrong person. They need to make the standard 16-20 loci. Also the tests can be contaminated fairly easily if the scientists and police aren't vigilant. This is more about the method of the lab that did the work. Read this article:
Yes, it is possible to be wrong with both. Both tests are less than 100% accurate, although DNA tests are generally much more accurate than polygraphs ("lie detectors"). In fact, many courts do not allow polygraphs anymore, because of their relatively low accuracy rate. If I remember correctly, the accuracy of polygraphs is OK, better than 50%, but not really good enough legal cases. DNA tests are typically much better, but there is still some potential for error. Forensic scientists typically look at regions of the genome (the complete DNA sequence of an individual) that are extremely variable, so that the probability of two people having identical sequences in a particular region are so low that the only reasonable explanation for a match is that the two DNA samples came from the same person. However, no honest geneticist would tell you it is IMPOSSIBLE that there could be a false match, the probability is just so low that it's unreasonable to assume that a positive match is really a false positive. In virtually all cases, if a DNA test is a match, that means that the sample came from the same individual. For example if semen or blood is recovered from a crime scene and it matches a sample taken from a suspect, the likelihood that that suspect was not the source of the body fluid is virtually zero.
Lie Detector tests are actually not foolproof (remember the George Costanza character from "Seinfeld" asserting: "it incredibly is no longer a lie in case you have faith it"). A polygraph try measures blood stress and coronary heart fee. it incredibly is a fallible technique. some each physique is in basic terms pathological previous perception (and the main probable criminals incredibly greater healthful the invoice).
Comments
Polygraphs are not even 50% accurate. Totally unreliable, hence why they're inadmissible in court.
DNA tests -- well it depends what they test. The 10 loci test is not enough, and it could fit multiple people and convict the wrong person. They need to make the standard 16-20 loci. Also the tests can be contaminated fairly easily if the scientists and police aren't vigilant. This is more about the method of the lab that did the work. Read this article:
http://articles.latimes.com/2008/jul/20/local/me-d...
Yes, it is possible to be wrong with both. Both tests are less than 100% accurate, although DNA tests are generally much more accurate than polygraphs ("lie detectors"). In fact, many courts do not allow polygraphs anymore, because of their relatively low accuracy rate. If I remember correctly, the accuracy of polygraphs is OK, better than 50%, but not really good enough legal cases. DNA tests are typically much better, but there is still some potential for error. Forensic scientists typically look at regions of the genome (the complete DNA sequence of an individual) that are extremely variable, so that the probability of two people having identical sequences in a particular region are so low that the only reasonable explanation for a match is that the two DNA samples came from the same person. However, no honest geneticist would tell you it is IMPOSSIBLE that there could be a false match, the probability is just so low that it's unreasonable to assume that a positive match is really a false positive. In virtually all cases, if a DNA test is a match, that means that the sample came from the same individual. For example if semen or blood is recovered from a crime scene and it matches a sample taken from a suspect, the likelihood that that suspect was not the source of the body fluid is virtually zero.
polygraphs aren't 100%, but with DNA you can get a match to 1 in 100 billion, which is about 10 times the population of the earth.
Lie Detector tests are actually not foolproof (remember the George Costanza character from "Seinfeld" asserting: "it incredibly is no longer a lie in case you have faith it"). A polygraph try measures blood stress and coronary heart fee. it incredibly is a fallible technique. some each physique is in basic terms pathological previous perception (and the main probable criminals incredibly greater healthful the invoice).