Thursday, 9 February 2017

A Queer Trace of Forensics

I love all those television programmes about forensic science, both factual and fiction, and so do millions of others. These days there are dozens of crime dramas and true crime series which deal with forensic detection.

Even though DNA testing has been around in crime detection since the early 1990s there is one particular technique developed by a gay forensic scientist which provides more plot twists than any other – trace DNA evidence.

We take it for granted these days that people leave microscopic traces of their DNA on objects they touch. That wasn’t always the case. At the end of the last century that gay scientist I mentioned, with the City of London Police and a Home Office agency, worked to create a means of obtaining DNA from microscopic trace, or touch, evidence obtained from hard surfaces.

The whole project was the brainchild of Dr. Nikolas Lemos (b.1971), a Greek-born forensic scientist who was until last year the Chief Forensic Toxicologist in San Francisco. By his own admission he was “the first ever openly gay chief forensic toxicologist in the world.”

In 1999 he was Senior Lecturer in Forensic Science at South Bank University in Greater London. In London at that time there had been a lot of computer thefts from some of the major financial institutions in the City. Millions of pounds-worth of equipment was stolen and police had difficulty finding the thieves.

Scientists had been using DNA found in dandruff, hair follicles and fingerprints as evidence in cases for several years. But what if there is no dandruff, hair or fingerprint? It was widely accepted that traces of DNA could be left behind on objects just by touch. But the technology to obtain DNA from evidence invisible to the naked eye wasn’t advanced enough. Nikolas Lemos believed you could obtain adequate samples if the DNA was put through a process of amplification (or duplication of DNA sequences) to provide one large enough to generate a profile. In standard DNA testing a sample of between 50 and 100 cells were needed to produce an adequate profile. The new technique developed by Nikolas Lemos at South Bank University, the City of London Police and the Forensic Science Service of the Home Office only needed 5 cells and is called LCN (low copy number) analysis.

It should be stressed that fictional crime dramas use over-simplification when featuring such techniques. In reality trace DNA identification by LCN is not without controversy. The technique is also not yet as widespread as crime dramas might suggest.
Despite its critics the LCN technique was adopted by the UK and has been used to provide DNA evidence in over 21,000 trials. Unfortunately, there have been some miscarriages of justice (as there can be if based on any other type of evidence) based on the LCN DNA used in some cases. Consequently, a review of the technique was conducted by the Crown Prosecution Service in 2007 during which time the technique was suspended for a couple of months. The review found that it was “fit for purpose” and reinstated.

More recently an American judge refused to accept LCN DNA evidence because he didn’t believe the technique had gained enough acceptance among the US scientific community.

By that time Dr. Nikolas Lemos had left the UK and had been Chief Forensic Toxicologist at San Francisco’ Medical Examiner’s office for several years. His work had always involved general forensic toxicology and the LCN DNA detection is just one part of Nikolas’s ground-breaking work.

Other high-profile work he had become involved with while in San Francisco was the study of the toxic effects of cannabis, and the toxicology report on the death of Whitney Houston.

In 2005 Nikolas received a Proclamation of Achievement for his “prestigious involvement in crime detection” from the United States Congress.

As an openly gay man Nikolas had campaigned for the legalisation of same-sex marriage, even going so far as to dress up as the Statue of Liberty and stand on the steps of San Francisco’s city hall. In 2013 he was nominated as a Grand Marshal of San Francisco Pride. Even though he wasn’t selected he again donned his Statue of Liberty costume to take part in the parade.

Dr. Nikolas Lemos left San Francisco’s ME office last year leaving a substantial contribution to crime detection and investigative techniques. Even though the LCN DNA technique he developed is not yet universally used it is a breakthrough that can only improve as science and technology advances.

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