Every criminal that the United States fails to convict on first offence goes on to commit, on average, an additional six crimes. It's a chilling thought, and it sits at the heart of one of the most pressing issues to face forensic science today; the DNA backlog.

The scale of the backlog problem has reached frightening proportions, with the latest Bureau of Justice Statistics indicating a 73% increase in case work, and a resulting 135% increase in case work backlogs, between 1997 and 2000 alone. And we're not talking petty crime either, with many of the unanalyzed DNA samples relating to sexual assault and murder cases. So what's at the root of it all?

The DNA backlog is currently affected by two key areas: case work sample backlogs from crime scenes, victims, and suspects, and convicted offender backlogs, from existing offenders that are either incarcerated or under supervision. Backlogs across both areas are growing substantially but without a related growth and expansion of forensic laboratories, the USA has been unable to cope.

As crime rates increase, this is an issue that is unlikely to dissipate, and potential legislation such as California's Proposition 69 will only magnify the problem.

Set to come into effect as of January 2009, the proposition will present the criminal justice system with the added pressure of DNA samples from arrestees, as well as convicted criminals. In short, the United States finds itself in a ‘Catch-22’ situation: on the one hand, the more DNA samples collected the more potential to solve crimes; on the other hand, the more samples collected, the more the backlog will grow. The U.S. is not alone in this challenge. The DNA backlog is increasingly becoming a global issue, with DNA centers in Australia also suffering serious backlogs.

Interestingly, the current plight of the U.S. backlog follows a similar pattern to what occurred in the United Kingdom. The challenge now is to utilize the knowledge and best practice available in the UK, here at the Forensic Science Service, and on a wider scale, and to use it to assist state investigators to tackle the backlog, efficiently and effectively, avoiding any prolonged and painful learning curves.

When it comes to DNA processing, the figures in the UK have improved dramatically, with over 0.5 million samples processed a year, each within a three to five day timeframe. And as analyzed samples have increased, our own FSS staff numbers have decreased as greater automation and efficiencies have been identified. But it hasn't always been that way.

The UK's national DNA database is extremely sophisticated. Following its launch in 1995, police and other justice bodies realized its full benefits and here at the Forensic Science Service where we looked after the database, we were bombarded with samples to the figure of 40,000 in the first year. But with a new system, came new problems, and within two years a backlog of some 135,000 samples had accumulated.

Eliminating the backlog clearly represents the most pressing problem, and technical understanding, management of information, and clear ownership are all critical issues. We were able to address the initial DNA backlog by re-evaluating our procedures, and seeking out the inefficiencies. It was only when we understood where bottlenecks and delays were occurring that we could accurately address them. This was achieved by reviewing and challenging our process and asking the appropriate questions: Is the current system fit for purpose? Do all staff members have the necessary level of training and competence?

From this review it was apparent that a backlog challenge of this scale could not be run through a traditional forensic lab with analysts taking samples from submission all the way through to interpretation. The only way to effectively manage the demand was to treat the process as a production line with staff responsible for specific parts of the process. Using this approach the FSS was able to increase staff levels with people who had the necessary skills, implement a 24/7shift pattern, and re-train existing staff where necessary. By modelling the revised procedures, we knew there would be a short-term increase in turn around times and through effective planning we were able to manage expectations of the police and Home Office, the UK Government department managing the criminal justice system. We now have a specialist group of in-house trainers that can cope quickly and efficiently with high demand.

The DNA backlog in the U.S. will continue to be affected by external developments such as changes in legislation and policy: Proposition 69 is a good example of this.

Back in 2001, the UK underwent a similar change in legislation, resulting in the power to retain DNA profiles if a suspect is acquitted. This, combined with a £300 million (approx $600 million at today’s exchange rate) Government investment into a DNA Expansion Program between April 2000 and March 2005, resulted in demand for DNA analysis doubling in just six months. In April 2004, the authorities in the UK then gained the power to sample suspects on arrest, and retain their profile, even when not charged. The result? Half a million submissions a year.

For us, managing the information and the processes remained — and still remains — critical but as the scale of the DNA backlog developed, our approach was also forced to develop. Thanks to various developments in technology and approach, we are now able to process each of the 0.5 million samples submitted every year, within a three to five day turnaround period, and with just 65 staff on the DNA lines. The opportunities are there for the United States to achieve similar or better.

Automation and the use of expert software systems present one solution that we are aware U.S. forensic scientists are beginning to investigate. Over the last ten years, the FSS has worked to develop robotics and wider technology to ensure that we are able to manage whatever level of samples we are presented with. From this experience we have learned a valuable lesson: it's not just about the technology but also about how you integrate it with the rest of the process, and feed it efficiently.

Using robotic instruments to remove mundane duties for staff has proved hugely successful, reducing the margin for error and contamination. But the use of robotics did represent a real leap of faith for our forensics teams – quality of programming is critical, and although we were using existing systems, we had to spend considerable time and resource designing protocols that told the machines to extract DNA, measure and amplify it as required to our forensic quality standards. As a result however we have been able to process an increased number of samples, in turn improving match rates. And because we can often match DNA from serious crimes to specific criminals originally recognized as committing minor offences, as the statistics show, we are able to help the UK police quickly identify, apprehend, and successfully prosecute likely suspects.

The same could be said of the actual interpretation of DNA profiles, which has also been greatly improved by technology, namely the use of expert systems. In simple terms, these expert systems are computer software that applies a number of scientific rules to the profile generated. After a series of tests, they proved more accurate than human analysts: something which was tested and proved over some 50,000 samples. The benefits of this in terms of quality, speed, and efficiency are impressive, and nowadays only 15 per cent of each batch is rechecked by a human analyst.

Operationally then, the parallels between the U.S. and UK are clear, and we hope that we can work in partnership with forensics teams in the United States to share and assess our experiences and assist in the future reduction of the backlog in the United States. But when operating in a world of science and analysis, it would be all too easy to forget the real impetus for change – and that's the safety and well-being of generations now, and in the future. The case example of the UK's Yorkshire Ripper Hoaxer however is a sobering reminder of the real link between backlog, convictions, and public safety.

In the 1970s, 50 year old John Humble, also known as the Yorkshire Ripper Hoaxer, sent three letters and an audiotape to police, claiming that he was the UK's infamous Yorkshire Ripper murderer. His actions led police to concentrate on a false line of inquiry, leaving the real Yorkshire Ripper to go on to murder three more women before he was finally caught in 1981. Thanks to advancements in DNA technology, John Humble has recently been tracked down, and sentenced to eight years in prison, after pleading guilty to four counts of perverting the course of justice. But what has this got to do with the DNA backlog?

Most of the original letters and envelopes were subjected to extensive chemical fingerprint testing at the time, but the radioactive sulphur dioxide used left them severely blackened and unsuitable for further testing. A few small pieces of one of the envelopes were retained by the Forensic Science Service. When the investigation was reopened by West Yorkshire police, it was possible to examine the fragments using the Low Copy Number (LCN) DNA technique. This can obtain a DNA profile from a sample expected to contain very few cells – even if it is too small to be visible to the naked eye.

The Hoaxer, John Humble was already logged on the National DNA database, as a result of a drunken driving charge years before. So when the LCN tests yielded a DNA profile and this was searched against the National DNA database, we were able to produce a single hit to a man in Northumbria, leading to John Humble's arrest and imprisonment. Had the database not been such a powerful investigative tool, and had the DNA backlog not already been addressed in the UK, he might still be on our streets today.

If there is one example that really brings home the social side of technological and legislative advancements then this is it – and there is a clear lesson to be learned. By addressing backlog issues, and supporting the justice system in either convicting or exonerating suspects, forensics teams in the UK and the U.S. alike have the power to help investigators solve major crimes, and make a real difference to the safety and well-being of our communities.

Putting any political and moral issues aside, the facts remain all too clear: the law in several states is set to change and with it, comes the greatest challenge that its forensics and law enforcement teams have ever faced. Address it, well equipped, and well armed, and with the lessons already learned in the UK, and it provides an incredible opportunity to put some of the most dangerous of today's criminals behind bars. Fail to do so however and the effects could be nothing short of catastrophic.

Richard Pinchin is Head of U.S. Operations, iforensic –a division of Forensic Science Service Ltd. He holds a degree in Biology from Nottingham University and is the author of several papers. Richard joined the Forensic Science Service Central Research Establishment at Aldermaston UK in 1988. In the late 1990s the concept of Intelligence Led Policing and the UK National Intelligence Model led to the formation of the FSS Forensic Intelligence Bureau which Richard managed.