1. What's the matter?
The National Forensic Center, NFC, is a department within the Police Authority that examines evidence from crime scenes.
SVT's revelation shows that NFC thins out large amounts of DNA evidence that ends up in a freezer in the basement - without fully analyzing the traces.
The reason is that NFC has a limit value, a stop for DNA samples: if the DNA content in, for example, a blood stain or a saliva trace is below this limit, no further analysis is usually performed.
2. Why is it a problem?
A German study, conducted on real crime scene tracks, shows that there are useful DNA profiles in more than one in three cases that fall below the Swedish limit value.
For over 20 years, NFC has had a limit value for DNA analyzes.
This means that there are a large number of incompletely analyzed traces in the freezer in the basement - traces that could contribute to trapping criminals or free incorrectly designated persons.
3. What does NFC say?
According to NFC's chief executive Helena Trolläng, NFC does not have the opportunity to analyze all the clues that the police send in.
In an email response, NFC writes: "The limit is set for not continuing the analysis of samples that NFC, during the validation of the method, has seen little or no chance of achieving a useful DNA result".