Tag Archives: forensics

Wonderful Things: Crime light

Looking back over the centuries, how many crimes committed back then would have reached a different conclusion if they occurred today with the use of modern science and technology?

 Advances in Forensic Science means that crime-scene evidence can be accurately gathered and examined, from collecting DNA and fingerprints to gunpowder residue from armed robbery, kidnap and murder.

 DNA profiling is a powerful tool in identifying a killer. Present in every cell, it identifies you and only you and it is what’s usually left behind at a crime scene.

 The Metropolitan Police estimate that they examine over 11,000 crime scenes each month and here in Who Am I? gallery, you will be able to take a look at a display of a real-life case that they needed to solve. The equipment that you will see was used by a team of forensic scientists who worked with the Metropolitan Police to solve the crime, using the latest DNA profiling technology and forensic science techniques, in particular a light source examination of the scene and objects.

 One of the items on display in this case is a crime light which was used at the scene and in the lab to detect body fluids. This LED forensic light source called Crime-lite uses filters of different colours along with viewing goggles to reveal blood splatters and fingerprint evidence otherwise difficult to detect just by looking. Providing intense, even and shadow free illumination for locating evidence, Crime-lite uses a white light for general search and seven narrow band wavelengths in UV, violet, blue, blue-green, green, orange, and red.

Crime-Lite- A Forensic's handiest tool?

Take a look at how a real forensic scientist from the Metropolitan Police North-West fingerprint lab uses this technology to detect and enhance hidden marks on a knife from a GBH incident.

  • Can you think of any infamous crimes that would’ve benefitted from a ‘Crime-lite’ or DNA profiling to solve the case?
  • Can we rely on evidence collected in this way? Is it always 100% accurate?
  • What could contaminate evidence? What preventative causes do you think police officers on the scene of a crime take to make sure they don’t disturb any evidence?

 Fancy letting your students having a go to see if they can solve a crime? Our KS3 Crime Lab kit contains three activities that covers scientific techniques related to identity and can also be used to solve our crime story about an attempted robbery at the ScienceMuseum.

To learn more about how DNA evidence can help us solve crimes, visit the Who am I? gallery on the first floor of the Wellcome Wing.

-Denise Cook

Wonderful Things: more than meets the eye

The toothbrush is ubiquitous in our homes; we pass it without consideration. But exploring the past of this toothbrush, a genuine item from ‘Ground Zero’, unravels a much larger, critical story.

Toothbrush used for the DNA profile identification of Alex Napier

This toothbrush has a story to tell. Image SSPL

The events of September 11th, 2001 need no introduction. These violent attacks altered our image of the world and left friends and families of victims wondering what had happened to their loved ones. In the aftermath, scientists, politicians and service people tried to answer these questions. Crucial to this was the Genes Code Corporation.

 The company worked alongside the New York City Office of the Chief Medical Examiner in the unenviable task of identifying the victims of the attacks;  every bit of remain, even the small pieces of tissue, had to be tested to allow families to complete burials.

Because of the severity of the event, the vast majority of individual remains had to be identified through DNA matching. Simple, everyday objects such as this toothbrush as well as items such as razors and clothing, were crucial in providing samples that might yield a billionth of a gram of DNA.

Scientists used these samples to produce the Mass Fatality Identification SYStem, MFISYS (pronounced ‘emphasis’).  This software recorded DNA profiles by sequencing genetic markers such as mitochondrial DNA (mtDNA), short tandem repeats (STRs) and single nucleotide polymorphisms (SNPs) then cross referenced this information with dental x-rays, DNA samples, and other important information to develop an account of missing persons.

Through these complex and painful searches, science helped to examine the facts and answer difficult questions. With debates surrounding projects like the DNA Database, many people are turning their attentions to the capabilities and possibilities of such resources- as well as the risks and ethical issues they carry.

Do your students think DNA profiling should be developed more or carefully moderated?

What else could we achieve by furthering the technology, and what problems can they foresee?

Where have you left your DNA today?

If you are planning a visit to the Who am I? gallery, look into booking the Great DNA Database Debate, our show about the national DNA database where your students can find out about DNA identification and voice their opinions in the debate.

 This toothbrush can be found in Who Am I? gallery. Wellcome Wing, First floor.

- Christopher Whitby