The World of Forensic Laboratory Testing

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Forensic testing isn't always the way it appears on TV.

On the popular TV shows, staff from a forensic laboratory solve a number of crimes within the show's hour-long format, presenting forensic testing as quick producers of irrefutable evidence that can be used in Court. But unlike the flashy, made-for-television scenario, real-life forensic laboratory analysis is much slower.

For example, when pop star Michael Jackson died in 2009, forensic toxicology testing took almost a month. That's not unusual. Tests can take weeks or even months to complete because of the technical and administrative requirements of different forensic tests, the limited availability or poor quality of some samples, the complexity of testing for illicit drugs, drugs used in therapy, and other toxic chemical agents, and the extensive record keeping necessary to ensure that reliable evidence is presented in Court. Sometimes tests are beyond a laboratory's expertise, so the laboratory has to send specimens to a more specialized laboratory to get the testing completed.

Forensic Laboratory Testing: What Is It?
Forensic testing is the gathering of data for use in legal proceedings, depending on the requirements of particular jurisdictions. "Both the requirement to keep very detailed records, and the scope and potential complexity of analyses that may be required in forensic laboratories are important differences from clinical laboratory testing” " explains Professor Robert Flanagan, consultant clinical scientist at London’s King’s College Hospital. Forensic laboratories have a certain way of handling samples, sometimes using specified testing methods as required by law, and always follow "chain of custody" procedures.

The chain of custody refers to keeping a record of every person who has had charge of a sample, what it has been used for, how it has been stored, and where it has been. Adherence to chain of custody procedure ensures that forensic laboratory evidence can be admitted in Court with the knowledge that the item was collected from a specified individual or location by a specified person and that the results obtained on testing the specimen can be traced back to the specified individual or location.

Laboratory staff who handle and process forensic specimens typically receive special training that is directed both to laboratory science, and to the legal demands of forensic work. Forensic laboratory scientists often have some clinical training, while forensic pathologists are qualified doctors who have received specific forensic training. Forensic pathologists conduct examinations on body tissues, blood, and/or other body fluids collected during a post-mortem examination (autopsy) or from a suspected crime scene and attempt to interpret the findings to help ascertain the cause, manner, and time of death, and sometimes to establish the identity of the deceased.

Investigation of deaths in England and Wales is the responsibility of the Coroner, who is appointed by the Ministry of Justice and must be legally qualified. The Coroner is empowered to require a post-mortem examination to be performed to find out the cause of death if this is uncertain, The post-mortem will usually be performed by a hospital pathologist, but if the death is suspicious the Coroner works closely with the police and a Ministry of Justice registered forensic pathologist will usually be appointed to perform or oversee the post-mortem and report the results. In Scotland, the Procurator Fiscal performs the functions of the Coroner, but also has an investigative role and not only directs any police investigation, but also acts as the prosecuting authority. Northern Ireland, the Channel Isles, and the Isle of Man also have separate systems.

In the UK clinical laboratories are accredited by Clinical Pathology Accreditation (UK), part of the United Kingdom Accreditation Service (UKAS). UKAS also undertakes accreditation of forensic laboratories. There are no specific standards of competence for individual forensic practitioners as yet in the UK other than pathologists, who undertake examinations to become Fellows of the Royal College of Pathologists and undertake further training before admission to the Ministry of Justice register.

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