[MUSIC] We said that forensic science is the application of science to criminal justice, but the boundaries are not so firm. The boundaries are actually quite fuzzy, because many of the concepts and ideas of forensic science can also be used in other areas, in other fields. For instance, they can be used in art. The picture on the right is a picture of the playwright William Shakespeare. And for many years it was believed that this particular picture really was a picture of William Shakespeare, painted by someone who either knew him, or actually was looking at him at the time. And that made it very valuable, because it was the only such painting in existence. Then someone did forensic analysis of the paint. They looked at the paint chemistry. They determined what kind of paint it was, and it turned out to be a kind of paint that had first been used in the year 1818, more than 200 years after Shakespeare died. So, it turns out that this painting wasn't so special after all, and we still don't know what Shakespeare looked like. Forensic science can also overlap with archaeology. We've said that forensic science can help you reconstruct the events of the past, and of course that is what archaeologists always seek to do and we will have a case study later on which illustrates this point. Forensic science techniques can also be important in sport. For instance, in major sporting events, there is drug testing for the athletes and this uses similar techniques that might be used, for instance, in a narcotics case. Forensic science can impinge on international politics. The picture on the right was taken at the site of a mass grave in Bosnia. These poor people here were killed as part of the Bosnian conflict and the investigators are trying to determine who they were, how they died, and who killed them. In addition, forensic science can come into play during disasters. In the 2004 tsunami that struck Aceh in Indonesia and Thailand and other places in the Indian Ocean, there were so many people killed, so many bodies, that forensic scientists from the region had to be mobilized to help with the identification. Forensic science, however, is not that new. It's roughly 100 years old. And one of the interesting things about forensic science is that it was being done in fiction books before it was actually being done in reality. So on the left, you see the instantly recognizable Sherlock Holmes. And if you read the Sherlock Holmes stories, you'll find a great deal of good forensic science in them. Curiously, Sherlock Holmes was not created by a forensic scientist or a police officer. He was created by Sir Arthur Conan-Doyle, who had just qualified as an eye doctor and started writing the stories in order to pass the time while waiting for patients to show up. And he turned out to be much more successful as an author than a medical man. [BLANK_AUDIO] We consider that the real founder of Forensic Science is this man here - a French professor called Edmond Locard. And here on the slide, you see a very substantial quotation which is attributed to Locard, and it really summarizes what Forensic Science is about. Talking about the criminal - "Wherever he steps, whatever he touches, whatever he leaves, even unconsciously, will serve as a silent witness against him. Not only his fingerprints or his footprints, but his hair, the fibres from his clothes. The glass he breaks, the tool mark that he leaves. The paint he scratches, the blood or semen he deposits or collects. All of these and more, bear mute witness against him. This is evidence that does not forget. It is not confused by the excitement of the moment. It is not absent because human witnesses are. It is factual evidence. Physical evidence cannot be wrong, it cannot perjure itself. It cannot be wholly absent. Only human failure to find it, study and understand it, can diminish its value." So, this is a very powerful quotation. And one of the most important parts of it is that final sentence. [BLANK_AUDIO] When forensic science goes wrong, when innocent people are sent to prison because of forensic science, it's not because the evidence, the physical evidence, the data collected from the evidence, is wrong. It's because of the human factor. There is a human error somewhere in the chain which has made that mistake. It's a very valuable quotation, but it's a very long quotation. So it's very helpful just to remember the short form of this quotation - "Every contact leaves a trace." And of course when Locard uses the term trace, he's thinking of the traces in his quotation there. Some of them are very difficult to observe. Fingerprints can be very hard to find. Fibres can be almost microscopic. Tool marks can be hard to discern. Blood or semen stains can actually be invisible to the naked eye. So many of these traces to which Locard refers to here, are very difficult to find. Sometimes, however, traces can be pretty obvious. Here's a curious case from the Times of London where a burglar managed to leave his false teeth behind. Now I have real teeth, I'm no expert on false teeth, but I think you'd notice if you didn't have them in your mouth. Here's another case, and it's a case I like very much because it actually comes from my hometown. My hometown is not the most interesting town in the world but this is one of the most interesting things that's ever happened there. And it concerns this Builders Merchants called Elliott, and around the back in their backyard, they had a big tank of diesel and somebody would climb over the back wall of the yard, steal some of their diesel. So the manager decided to do something about it, and he put razor wire on top of that back wall. So, soon after, when the first employee came in one morning and went around the backyard, he noticed something rather unpleasant on the razor wire, and it was a finger which had been cut off. Now this was a very easy crime to solve, because it's a pretty obvious trace and all the police had to do was to go around to the local emergency room and ask them if they had anyone there with a finger missing. And the culprit was subsequently arrested and convicted of this crime. [BLANK_AUDIO]
