Special Reports

WHEN the torso of a young boy was found in the Thames in September 2001, the police were unable to identify the victim of this horrific killing. The key to the crime was the child's recent whereabouts. He was evidently of black African origin, but was he from the UK or abroad? Forensic scientists were brought in to unravel the mystery. "It was a question of geography rather than ethnic origin," says Layla Renshaw, a forensic archaeologist at Kingston University in Surrey, who was a member of the investigative team.

In fact, the scientists were able to answer this question. Traces of pollen in the boy's stomach showed that he had been in Africa until shortly before his death, and the isotope signature of his bones allowed geologists to narrow down his home to a region of Nigeria just 160 by 80 kilometres.

The ingenuity of crime scene investigators in cases like this has led to a surge in popularity of careers in forensic science. And it is a growing field. The number of samples sent for forensic analysis by the police has doubled in the past five years, and the British government has committed £182 million to increase the number of DNA profiles from suspects and crime scenes.

But despite this boom, there are still no more than about 10,000 forensic science positions in the UK so employers can pick and choose. "When I was head of forensic science for Lothian and Borders police we had between 200 and 300 applications for every post," says Allan Jamieson, who now chairs the academic and education forum of the Forensic Science Society.

The police is the main employer. When a crime is committed, scenes of crime officers, who are usually civilians rather than police offers, are sent to gather forensic, photographic and fingerprint evidence. This is predominantly a non-graduate job, but one that is growing more sophisticated as new technology plays an increasing role in the collection of evidence.

This evidence is then sent for detailed analysis at specialist labs, and it is at these that graduates are most likely to find a job. The Forensic Science Service (FSS), which is an agency of the Home Office, is the biggest employer in the field with around 1600 forensic scientists. Between 2001 and 2002 the FSS worked on evidence from 130,000 cases. This involves anything from analysing cigarette butts left at crime scenes to identifying drugs seized by the police. The FSS also runs the National DNA Database, and generates many of the DNA profiles that it contains.

In recent years, the market has opened up as private companies have started to compete with the FSS for this kind of work in England and Wales. One of the biggest of these commercial outfits is Forensic Alliance, based at Abingdon in Oxfordshire. As well as offering a complete range of analytical services in biology, toxicology, drugs and chemistry, it has recently broadened its horizons with the launch two years ago of an ecology division focusing on entomology, palynology (pollen analysis) and archaeology. The company employs 110 scientists and has doubled in size every year since it was founded in 1997.

Another competitor is LGC, formerly the Laboratory of the Government Chemist, which is based in Teddington in south-west London. It is growing too, and now has about 100 scientists in the forensics division out of a total workforce of 600. "We have been expanding our DNA staffing to meet demand for producing profiles from crime-scene stains as well as routine screening of mouth swabs for inclusion in the National DNA Database," says Ric Treble, a forensics business manager at LGC. But it's not all about DNA. "Other major activities include drugs analysis, toxicology, and forensic examination of documents, computers and mobile telephones," he says.

In Scotland, a different system operates, and the major forensics labs are run by police forces, employing around 120 scientists.

But what does the job of forensic scientist actually entail? "It's about interpretation, evaluation and presentation of scientific evidence," says Jamieson. Scientists work in their specialist areas to analyse anything from biological stains to paint, explosives to narcotics - sometimes visiting the crime scene too. Forensic skills come into play in interpreting results in the context of a crime and in giving evidence in court.

It's painstaking work. "You can concentrate on a piece of evidence for four hours at a time," says Abigail Bradley, forensic account manager at Cellmark, also based in Abingdon in Oxfordshire, which carries out DNA analysis on behalf of its partner, Forensic Alliance. After taking a biomedical science degree at the University of the West of England, in Bristol, she started as an assistant forensic scientist with the FSS. On a six-week fast-track course she trained in analytical techniques such as PCR (the polymerase chain reaction used for amplifying DNA), genotyping and crime-scene item examination - and despite the routine nature of the work, she loved it. "It was very exciting, actually dealing with people's lives," she says. She then moved to the private sector, working as a forensic scientist with Cellmark, before taking up her present post.

Talk to anyone involved and they all agree that it's nothing like what you see on TV. "People come in with a myth about what goes on. The work is highly regimented and very carefully controlled," says Brian McKeown, technical development manager at Cellmark (see "Case Study: Gene frontiers"). "The results must stand up in court," he points out.

The work demands very high levels of technical expertise. "You must treat every sample like it's the most important you'll ever do, like you couldn't do it any better," says McKeown. "We are dealing with people's liberty".

You can get a foot in the door without necessarily having a qualification in forensic science. "Employers are looking for good scientists who can be given the necessary training in order to assess evidence to make a forensic case," says Jamieson. But a qualification in the field may give you an edge. And maybe this is the reason for the explosion in the number of university degrees with "forensic" in the title. A staggering 313 such courses are on offer this year.

The plethora of new courses has led to questions over whether they can deliver the standard of training needed to work as a forensic scientist. "Initially I was very resistant to these courses," says Jamieson. "But now I take the view that we will try to assist universities to deliver certain standards of forensic science training." The Forensic Science Society hopes to launch an accreditation scheme by the end of the year.

Even now, a qualification in forensic science is no guarantee of a job. This is something that Renshaw, who is setting up a forensic science course at Kingston University, is fully aware of. "We have to run our course responsibly and manage student expectations," she says. "Students should think broadly. There are options other than the FSS: the insurance sector, for example, or fast- track entry to the police." And a growing number of smaller outfits offer expertise in everything from document examination to fire investigation and forensic telecommunications.

Be prepared to face tough competition if you are thinking of becoming a forensic scientist, and some painstaking work once you have a foot in the door. But the rewards will be great too. As Bradley says: "When you know you have processed the samples that helped solve a crime, it's fantastic."

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