Impression Evidence – PowerPoint Presentation

Impression Evidence

There is a lot of evidence left at a crime scene and it can range from shoe impressions to tire tracks, bite marks and other items. A tire track can be very helpful to an investigator. Sometimes the investigator has to look hard to find the smallest piece of evidence.

Impression Evidence (Cont.)

When photographing an impression they should be made using a tripod, ruler, and a level. The flash needs to be held at a 45 degree angel from the surface. A tire impression can tell the investigator what type of tire it is.

Impression Evidence (Cont.)

When a person is committing a crime he or she may not think about the types of evidence that they can leave behind. Evidence such as a chewed piece of gum may contain DNA. Evidence that may contain DNA is a smoked cigarette butt.

Impression Evidence (Cont.)

Upon arriving at this crime scene which appeared to be a robbery there was an open door. The door appears to have some marks on it from possibly a crowbar used to open it. The door will be photographed.

Impression Evidence (Cont.)

A special light may be needed to see a shoe impression. To life a shoeprint an electrostatic dust-print lift may be used. This type of lifting is the best method for collecting dry or dusty residue impressions on almost any type of surface.

References

Delattre, J. E. (2011). Character and cops: Ethics in policing.(6th ed). Washington, DC: AEI Press.Fisher, B. A. J., & Fisher, D. R. (2012). Techniques of crime scene investigation. (8th ed). Boca Raton, FL: Taylor & Francis Group CRC Press.Foster, R. E. (2013). Police technology. (1st ed). Upper Saddle River, NJ: Prentice Hall.