Forensic science is nowhere near as robust and reliable as many people think
We all want to live in a world where there is justice; where wrongs are righted, where the system is trustworthy and just works. But we have seen a growing body of reports that raise questions about that system. I was particularly challenged when I started doing research that was based on a murder case tried in 2002, which centred on the presence of trace particles on the victim and in the suspect’s vehicle. In court, the jury heard that these particles were very rare and wouldn’t last on clothing for a very long time – just for a matter of minutes. This indicated that the victim must have made contact with the vehicle seat shortly before their body was deposited at the site where they were ultimately found. On this basis, the jury delivered a guilty verdict. When we started exploring and carrying out some experiments on these particles we discovered that they were in fact not rare, but abundant. And they lasted a long time on clothing – many hours rather than minutes. The significance of these particles in that case was completely changed by a series of experiments.