Planted dna?

[curious4]

The murder of a young girl in Sweden has been widely publicised. A man has been found guilty of killing her, mainly on the basis of dna evidence. He claims he is innocent and the dna was planted on his clothes. Does anyone know whether this is possible? And if so, how?

Best wishes
C4

[Pcdunn]

The murder of a young girl in Sweden has been widely publicised. A man has been found guilty of killing her, mainly on the basis of dna evidence. He claims he is innocent and the dna was planted on his clothes. Does anyone know whether this is possible? And if so, how?

Best wishes
C4

Hmmm... I think it would depend on who had access to both his clothing and his hair, skin flakes, etc. Spouse or housemate?

If he's claiming the police planted it-- they'd have to had already taken a sample of his DNA first, wouldn't they? I mean, they might collect his clothing and take it away for testing, but if they didn't have the guy's DNA sample already, they couldn't plant it. And testing takes longer than in the TV dramas, of course...

[Errata]

If her DNA is on him, but his is not on her, that's certainly a little odd. Not unsolvable, just kind of odd.

But it's possible. Not likely, but it can be done if a bunch of conditions are met. It has been demonstrated to be possible. And cross contamination in labs used to be kind of a thing, so if it could happen accidentally, it can happen on purpose.

[Rosella]

Wasn't it said by Hanratty supporters that his DNA was transplanted, presumably by police, on to a hanky of his and on to Valerie Storie's knickers during a DNA test in the early 2000's?

[caz]

Not quite, Rosella. See the A6 topic for more info (a lot more info ).

Hanratty's supporters have come up with all sorts of innocent explanations, but I'm not sure even they have gone that far. His remains were not exhumed until earlier, inconclusive tests (which Hanratty's supporters had campaigned for) had indicated a match with close relatives. The DNA extracted from the hanky and knicker fragment was therefore already in situ before forensic examiners had access to DNA from Hanratty's remains.

The main argument tends to be that the samples could have become contaminated during storage (while the real killer's DNA, deposited first, is meant to have degraded without leaving a trace).

Love,

Caz
X

[caz]

Hi again Rosella,

If you are interested in the Hanratty case, and the DNA evidence, have a look at the 2002 Appeal Judgement here:

http://www.bailii.org/ew/cases/EWCA/Crim/2002/1141.html

Love,

Caz
X

[curious4]

Hello and thanks to all. I was thinking along the lines of the real murderer planting dna from someone else to frame someone else for the murder. The main dna evidence is traces of blood on the victim's clothes. She was apparently strangled with a rope and less reliable dna traces were found on some pieces of rope in the barn where the murder took place and where the accused man worked and left his working clothes. He claims that he often injured himself working with tools etc. It is a bit farfetched I suppose, but could blood traces be moved from once place to another by using, say, a damp cloth?

Best wishes
C4

[Errata]

Hello and thanks to all. I was thinking along the lines of the real murderer planting dna from someone else to frame someone else for the murder. The main dna evidence is traces of blood on the victim's clothes. She was apparently strangled with a rope and less reliable dna traces were found on some pieces of rope in the barn where the murder took place and where the accused man worked and left his working clothes. He claims that he often injured himself working with tools etc. It is a bit farfetched I suppose, but could blood traces be moved from once place to another by using, say, a damp cloth?

Best wishes
C4

I don't think you could remove the traces of DNA from one thing and transplant that DNA to another thing. I think DNA will always be on both things. But yeah, if you really wanted to you could spend the time muddling the DNA of the scene pretty effectively if you had a source of foreign DNA.

[Robert]

Were his tools checked for his own DNA?

[Shaggyrand]

Are you talking about the Lisa Holm murder? The guy's blood was found on her clothes and the rope she was strangled with, his semen was also found in the barn where she was killed.
In theory, I guess the blood could be planted if lifted off a tool with EDTA or another medium, even scrapped off on to clothing and the rope, and placed elsewhere. Though I would also assume that it being lifted a second time, if they'd used a chemical to get it, by a crime scene tech would greatly damage the sample and make it unusable. Getting his semen would be a bigger hassle, don't think borrowing his wankie hankie and rubbing it around would do the trick- not well enough to raise questions if folks are doing their job properly.

[Ginger]

But yeah, if you really wanted to you could spend the time muddling the DNA of the scene pretty effectively if you had a source of foreign DNA.

I read a story once where the murderer vacuumed the lobby of a busy office building, then spread the contents of the dust bag around the murder scene.

[Errata]

I read a story once where the murderer vacuumed the lobby of a busy office building, then spread the contents of the dust bag around the murder scene.

I swear I read that and sneezed.