Sample Essay on Potential DNA evidence at the scene of crime

Potential DNA evidence at the scene of crime

           Potential samples

  • The Blood stains, Semen, Saliva, Urine, Hair with hair root, Teeth, Sweat, Body tissues and cells.
  • These samples would be obtained mainly from the window where the culprit got access into and the bed where the crime took place.
  • Apart from the samples, other items would include; the knife, bed sheets, masks, gloves and clothing that might have been left behind by the culprit
  • Since as it was a rape case which involved struggle, the culprit most probably left some small traces of the listed samples on the bed and the window known as touch DNA.

Ways of collection

  • Some of the precautions include that need to be taken; wearing of protective gear like the gloves and making sure that the samples  are free from contaminants as dust as much as possible, samples should not come into contact.
  • Photographs at the crime scene of  various samples and  specific  areas are taken clearly in all dimensions.
  • Measurement of the knife and the window used by the culprit is also necessary to extract vital information such as the body size estimation of the culprit.
  • Liquid  elements from the crime scene  like blood  are taken by use of swabs, gauze  pads or disinfected cotton wool, dried, put in a paper bag or dry box sealed and labeled to be taken to the laboratory. Liquid samples can also be collected with a clean syringe, Samples on the garments and the knife should be collected  separately with the whole item.
  • After collection of the samples, proper storage is essential as biological samples like the blood is known to bio-degrade easily. Room temperature condition is mostly recommended.