As a follow up to his report on DNA and Omagh last night
Michael Buchanan returns to the subject in the programme tonight. He writes:
David and Terry Reed were convicted of murder at Teeside Crown Court in August of this year and given life sentences. The trial judge said the forensic evidence against them, the controversial Low Copy Number Test that was heavily criticised in the Omagh verdict, was "absolutely critical". We've been looking at the case for several weeks, and it seems there are some questions about the brothers's conviction."
I am a criminal barrister.
What you will hear said in defence of this procedure, (I heard it this morning) is that it will "normally only be used where there is 'some other evidence" against the defendant.
What is not immediately realised about this apparantly ballanced andf fair remark is that it is in fact saying ... well as long as there is something else that can be said against the defendnat, we can justify using unreliable evidence to support it.
Unreliable evidence is unreliable whatever the circumstances.
J davies @ 1
PLEASE, give-up the criminal part of your activities
Barrister's should not, by definition, be criminals...
From what I understand of the procedure, the scientific technique is pretty good at what it's supposed to do - multiplying small amounts of DNA to a level whereby its sequence can be analysed.
However, the problem appears to be in how the police are interpreting the results.
It doesn't take a degree in science to realise how many different people's DNA might be attached to your clothes. Washing clothes might not get rid of 100% of the DNA strands on them, so the jumper you're wearing at the moment might have the DNA of people at the yarn factory, the factory where the yarn was assembled into the jumper, the people who delivered it to the warehouse, the people who delivered it to the shop, the shop floor staff, the customers who've handled it (and possibly tried it on) before you.
Even if your washed it and got rid of all DNA traces, since you started wearing it, it might have aquired the DNA of your friends / relatives / pets, plus anyone who's touched you while you're wearing it...
And for a recently deceased person, add on the police and the pathologist.
Oh yes, and whoever killed you as well.
So how do the police verify that the DNA they've got is from the killer, rather than one of the oodles of completely innocent people who've been in contact with the victim recently?