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ChadTower:

Do a little reading on DNA matching technology, then do a little reading on the legal concept of reasonable doubt.

They cannot pull nearly as much of a DNA sequence from most crime scene evidence as you seem to think they can.

tommy:

--- Quote from: ChadTower on December 27, 2007, 11:25:37 am ---
They cannot pull nearly as much of a DNA sequence from most crime scene evidence as you seem to think they can.



--- End quote ---


That depends on the case. Either they have enough DNA to test or they do not, and they tell you when they do not have enough evidence to make the call. I'm talking about cases when they do.

CCM:

--- Quote from: tommy on December 27, 2007, 11:27:54 am ---
--- Quote from: ChadTower on December 27, 2007, 11:25:37 am ---
They cannot pull nearly as much of a DNA sequence from most crime scene evidence as you seem to think they can.



--- End quote ---


That depends on the case. Either they have enough DNA to test or they do not, and they tell you when they do not have enough evidence to make the call. I'm talking about cases when they do.

--- End quote ---

Not quite...

http://library.thinkquest.org/04oct/00206/text_pti_dna_matching.htm#pti_accuracy



--- Quote ---The Accuracy     
Top^

DNA databases have built a reputation as being a fast and efficient way of solving crimes. The identity of an individual is encoded in a database using a compilation of numbers no longer than four telephone numbers, making it extremely simple to match the numbers from the criminal with the numbers from the crime scene.

DNA matching is however, constantly under question when used as evidence in court, as contamination of a sample is possible, even though strict precautions are put in place to prevent contamination. For example - a stain containing DNA was found at a crime scene in a country that has a population of 10 million people, and the crime scene DNA sample is accurate enough to match 1% of the population. A suspect is arrested and that person's DNA sample matches perfectly with the one found at the crime scene. The prosecutor argues that because only 1% of the population shares the same DNA profile, there is only a 1 in 100 chance that the person is innocent. The defence however, then argues that if 1% of the population share the same DNA, then there could be 99 999 (1% of 10 million minus 1) other individuals who could have possibly been at the scene of the crime. Presuming innocence, the odds of the suspect being guilty are actually 1 in 100 000. This example shows the hazards of relying too much on DNA as evidence.

If there is enough evidence to support the DNA sample, then this amplifies the suspicion of guilt and makes a very persuasive case. However, if the there is little or no evidence to support the DNA sample, then the sample is practically useless.

--- End quote ---


DNA alone isn't enough to prove anything....

tommy:
Well that link helps me more than it hurts me. I never said rely on DNA only, but it does show very good proof when a person who said they have nothing to do with a crime and has left his DNA behind in a place that does not seem to be right can prove a lot.

ChadTower:
They can't say "he left his DNA behind".  They can say "someone with a DNA profile like his left DNA behind".  Look at the numbers.  All it does is prove that someone in a group that also includes the defendant was involved.  A very, very large group that probably includes Jeremy Shockey.

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