Zoom and enhance images. That's never going to happen.

Please, if you make CSI-type programmes, stop doing it.

I think, probably, a lot of what you think about what happens

at a crime scene is determined by what you see on TV.

And oh my, the reality is so much different.

Zoom in right here on this spot.

Enhance the reflection in her eye.

The reflection of the man's face. The reflection. There's a reflection.

There's a phenomenon related to forensic science

known as the CSI effect.

Legal professionals, in particular, started getting concerned that

that was affecting real people that were serving on juries in real cases.

Because TV is so immediate, you're actually seeing it,

it has an extremely powerful impact.

Verging on the dangerous side.

They were concerned that if there wasn't the type of evidence in a case

that you would see on the TV that the jurors would think,

{\an2}"Well, it's a weak case." They were also concerned that

the presence of some evidence, even if it was fairly weak evidence,

would be seen by jurors as being very strong evidence because it's got the

word forensics in it, and forensics on TV means you've solved the case.

Forensic science is really any form of science that's applied to

the civil, sometimes, but usually criminal justice systems.

Physical forensics is physical items - blood, skin traces, hair, fibres...

that sort of thing. Digital forensics is things like phone records,

digital information as well, which will tell you, for example,

when the recording was made.

It's not used all the time. It is still slow.

There aren't always the resources that we need.

And it's not always appropriate.

ARCHIVE: The advent of the electronic age has changed all that.

But there are still some things that we just cannot do.

Facial reconstruction is most of the time fiction, you can't say,

{\an2}"Oh this is the person," just from the skull.

This is just so much like... chunky bits.

Bite mark analysis, er, that's probably fiction.

Were you able to determine which monkey bit him?

The bite marks match those of the monkey found at the scene.

You're comparing part of a print...

… which is usually quite a rubbish smudge mark ...

… to a whole set of fingerprints and trying to make a match.

Eight million people just in central London.

That's so many other people who can be prosecuted.

CLIP: Well it turns out his fortune can be read from his palms.

It's also worth bearing in mind,

forensic evidence is circumstantial evidence.

Forensic science has said, "Yes, this person is present,"

does not necessarily mean that that person has committed the offence.

The Phantom of Heilbronn.

The Phantom of Heilbronn, it's a very interesting case.

I'll simplify this massively. The police were finding DNA traces

from an unknown person at a huge number of different crime scenes.

So many across Europe panicked law enforcement.

And they started to think,

{\an2}"Have we got a serial killer on our hands here?"

DNA can only tell you what you ask it to tell you.

The data are what the data are.

But what the data mean is always a matter of judgement.

Even if it is a suicide note, that doesn't mean it's a suicide.

Yes, I know that Detective Constable.

I think there is possibly a tendency for people to want science

to have the answers.

Caution should be part of the craft,

which is not really the case on TV shows.

It is important to establish both the certainty and the uncertainty.

Is forensics fact or fiction? That's...

This is going to sound rude...

I can kind of forgive the fast-forwarding of how long it takes

to actually do forensics.

I think human beings are hardwired to find out what happened.

We all love secrets. We all love mysteries,

we all want to work it out.

So are you happy for my answer to be, "It's both."

So, where science can come in and say,

{\an2}"Hey, you've got that wrong. Let's put it right."

That's a tremendous advantage. And of course, if it can come in in

the first place and go, "Hey, don't get that wrong," that's even better.

Thanks for watching! :)

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