Finding archeological clues at crime scenes

Understanding how a person died can be important historically. But nowadays, this information is vital in cases of crime, mystery or wrongdoing. The first clue in these investigations are often found at the scene and it is the role of forensic archeologists to help find and carefully excavate these areas. Trying to visit a real crime scene is pretty much impossible, but we came to the closest thing; a mock-up burial site. This is set up for students at Cranfield University to learn how to work on these precious and sensitive scenes. Nicholas Marquez-Grant, a forensic expert at Cranfield, first set Julia Ravey out on a task to try to uncover the scene of a crime...

Nick - Intelligence says that a few weeks ago, two mass graves were created in this location. Some mass graves that are, say the size of a tennis court, more or less.

Julia - Well, there's a big piece of ground here that's not got a grass on it. Am I getting warmer?

Nick - Exactly what we're seeing is that there's an area where the grass has been cleared. There's no vegetation. We've got soil and this soil we know is usually found about meter in depth in this location. So it means that something has gone in and resurfaced this soil. And you can also see some tyre marks there from either a lorry bringing bodies or even a mini digger. And it's got the right size according to the number of disappeared that we know. So in fact, if you look at the rest of the area, basically I should give you a Masters already. It's approved. I would start digging this location as the most likely for that mass grave.

Julia - What would be the next steps?

尼克-往往发生在什么场合,prior to digging up this, we might take some samples of the vegetation and the soil, because that soil may be linked to say a car vehicle, some footwear analysis. And we'll try to find the boundary of that mass grave. So we'll probably define this area a bit more by hand. And then we may go with a machine and we look out for any changes in the soil - any colour changes. If there's any discovery of clothing or any human remains, we'll stop the machine and we'll start digging by hand. We are going to document the position within the grave. They'll be lifted. And once you've emptied the grave and you've recovered all the human remains, you still continue digging because in the base of the grave is where you may find more evidence

Julia - Over the field, Nick's colleague Roland Westling was busy digging up the earth. So we went over to see what was going on. We're sort of out in the sticks a bit here, aren't we? And I'm now faced with a few different plots. What's going on right now?

Roland - We are basically standing next to two shallow graves that are going to house a victim each, and there's a very complex scenario behind it, we've made a massive story up.

Julia - And so at the minute in the grave, there looks like there is a t-shirt and some trousers. Is anything else going to be going into there?

Roland - I'm just basically putting ribs and vertebrae into the polo shirt. There's already a skull underneath and the legs. So this body has essentially been dismembered. But each of the graves is essentially going to house a slightly different body. There will be a link between all of them. So there will be something that is going to link them to the same perpetrator.

Julia - And when you're putting the body in, are you putting in any other clues? So like the way the graves have been dug, or any other bits of evidence that they have to find to piece together, what's gone on?

Roland - Some victims will have artifacts on them like a mobile phone or a receipt.

Nick - And as we're digging out where you can see these tool marks, so we can tell it's obviously hand dug, potentially the spade. You can cast this or photograph it or so on. There's a few other scoops around there. It's pretty similar, I think, to some of the cases that may have been encountered in the past in criminal investigations.

Julia - Very interesting. It looks scarily accurate. I'm sure that some of the planes flying overhead must look out the window and go, 'What's going on here?'

Nick - Of course they are plastic skeletons. Don't try this at home!

Roland - But they can look very realistic.

Julia - Well, I'm guessing there's a lot of work to be done here, so I'll let you get to burying the bodies.