It was not anyone who took the witness box in the Haugaland and Sunnhordland District Court on Thursday morning. Professor Walther Parson from the University of Innsbruck is known as one of Europe’s leading experts on DNA. He has published over a hundred research articles in the field of forensic medicine and forensic genetics, and he has been awarded a number of international prizes. Parson has assisted in the investigation into Birgitte’s murder since 2001. And he was clear in his conclusions. In 2017, the experts in Austria received a new request from the Norwegian police. Among the samples they were asked to re-examine was a test tube containing material that had been frozen for over 20 years. The sample came from Birgitte Tengs’ pantyhose. During the investigation in the 90s, a bloody piece of the pantyhose was cut out, but at the time no trace of a possible perpetrator was found. But three and a half years ago, Parson and his colleagues were able to report a breakthrough. They were now able to determine that the sample also contained a so-called Y chromosome, i.e. remains of a male DNA. The find was thoroughly scrutinized, the experts used, among other things, two different and completely new analysis methods. And it gave results. The professor explained in court how they finally got a match between the Y chromosome and the DNA profile of the accused 52-year-old. The Y chromosome is only found in men, and the chromosome found on Birgitte’s pantyhose comes from the father’s line in the defendant’s family. At the same time, a rare mutation has occurred between the defendant and his father. According to the experts, this rules out that the Y chromosome can come from someone other than the defendant. In addition to the two new methods, Parson and his people also used a third method to double check whether they could still rule out the 52-year-old. They couldn’t do that. The results are of great value to the prosecution. The entire indictment in the murder case is based on the DNA experts’ findings. Put another way, the case would never have come to court without the breakthrough at the laboratory in Austria. The prosecution believes the discovery confirms the theory that it was the perpetrator’s fingers that deposited a bloody stain on the pantyhose, and at the same time left some of his own skin cells. The prosecution’s main problem is that they cannot support this theory with other evidence. In court on Wednesday, the experts from the Forensic Institute in Oslo were asked about the theory about the perpetrator’s bloody fingers. They could not substantiate it. “The DNA result only says something about who it comes from, not how it was deposited,” said forensic geneticist Gro Bjørnstad. The Norwegian experts also warned against relying too much on DNA as evidence in the case. “DNA should not, and should not, be the only evidence in a case”, stated former section leader Bente Mevåg. She added that the smaller the amount of DNA involved, the more important it becomes to be able to put the finding into a context. Thus she was at the heart of the matter. The prosecution believes that the accused murderer’s DNA can only have ended up on the pantyhose while Birgitte Tengs was killed. The defenders in the case maintain that the finding lacks context, and that it therefore leaves more questions than answers. The lawyers believe that there can be a number of alternative explanations for the DNA discovery, and that only the imagination sets the limits. In particular, they point to possible infection or transfer of biological material before the murder, or that there may have been an accident in the handling afterwards. For example, during one of the case’s many laboratory examinations. Prosecutors have gone to great lengths to close the door on these possibilities. The defense are right that little is known about the accused and Birgitte’s movements on the day of the murder. However, there is nothing in the case to indicate that they were close to each other. Nor has it been established that DNA or seizures from the accused have been analyzed at the same time as evidence in the murder case was examined. But one can hardly be completely sure in such an old matter. The investigation and crime scene routines of the time were completely different. Little was known at the time that a tiny amount of DNA would become the subject of week-long discussions in a courtroom in Haugesund 27 years later. The question thus becomes whether the doubt is so great that it opens the way for an acquittal, or whether it is really only theoretical. That question will be decided by the judges only once over the New Year.
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New methods can bring down the accused of murder – Statement
