Aggregated News

Potential for the contamination of forensic DNA evidence has been highlighted by the Meredith Kercher murder trial. But just how much of a problem is it and what lessons should be drawn?

The high-profile retrial of Amanda Knox and Raffaele Sollecito, who had been imprisoned for the killing of Meredith Kercher, has placed renewed scrutiny on the DNA analysis carried out in the case.

An Italian court has now reinstated the 2009 guilty verdicts which were overturned on appeal in 2011, handing down a sentence of 28 years and six months for Knox and 25 years for Sollecito.

During the retrial, the judge ordered a new DNA test on the knife that prosecutors had submitted as evidence.

But some independent forensic scientists told the BBC this knife (which had been considered a possible murder weapon) should never have been given the importance it was because there was no evidence of blood found on it.

Greg Hampikian, from Boise State University in Idaho, US, is one of them. The forensic expert is critical of the way DNA evidence was handled.

"I...