Peter Sjölund, genealogist and DNA expert, has together with the police in Linköping made it possible to call in the suspect killer with the help of a new effective method, which is based on family databases.

- Police tests, they test 15 markers in the DNA while we test 700,000 markers, so it's incredibly much more powerful, says Sjölund in Wednesday's News.

Suspected DNA is not needed

Normally, with the technology used by the police in Sweden, a suspect's DNA is needed to match a track on a crime scene. But with the help of the method used in Linköping in the double murder case, they managed to call in the suspect without first having his DNA.

Peter Sjölund explains:

- Police tests can clearly show that this person is the same as this track, but we don't even need a person.
It doesn't even have to be close relatives, it can be the roars or relatives of many generations. And then with the help of them we can call this person even though we do not have this person's DNA from the beginning.

"A giant revolution"

That you can now find a killer in one of Sweden's most talked about murder cases with the help of this method, where you use large databases, which are normally used for genealogy, is just the beginning. 

- This is bigger than the fingerprint, a giant revolution really. This is a pilot project, but I see that this can become a standard method that can solve more and more difficult crimes.