– Tool Mark Analysis
Scenario: A string of car burglaries and house burglaries were happening in a very affluent neighborhood at a rate that had already doubled the number of burglaries from a year ago. It seemed as if the method of operation that was being used to commit these crimes was consistent with one another, but there were no witnesses to the crimes. The car burglaries were committed in the early morning hours when most victims were asleep and the house burglaries were being committed during the day when most victims were at work or away from the house. The police department felt that the crimes may be connected, so they assigned one of their more experienced Crime Scene Investigators to be assigned to reviewing the physical evidence that had been collected from the previous crime scenes and all future burglaries where it seemed that they fit the same pattern.
During the initial analysis of the physical evidence that was collected and preserved from previous crime scenes, the Crime Scene Investigator noticed marks that she felt were consistent on the car doors when they were pried open and on the doors and windows entering the homes that had been burglarized. The marks appeared to have been made by a crowbar or a large screwdriver.
Two weeks later Investigators got a tip from an informant that a group of High School boys had been bragging around school about how they were being modern day “Robin Hoods”. They said that “They were stealing from the rich and giving to the poor”. The Investigators went to the High School to question the boys about the burglaries. Each one of the boys denied any involvement at all. The Investigators asked the one boy that had a car that all the boys normally rode around in, if they minded if they took a look into the car. The owner of the car said it would be perfectly fine.
When the Investigators opened the trunk of the car, they saw several different crowbars and screwdrivers that appeared to have small chips of paint on them. They also observed numerous pairs of large pliers that also appeared to have small chips of paint on them as well. Is there a way to determine if the tools found in the trunk could have been used to commit the crimes? Can the tools be positively included or excluded as the tools that could have been used? Do different tools leave the same marks or do they leave different marks when they come in contact with surfaces that are made of different types of material?
This audio will answer these questions in great detail and show this evidence can be used as great circumstantial evidence that could prove very important in a court of law when a criminal case is being prosecuted. You will learn about the different types of tool marks that are recovered from the crime scene and what the limitations are of their results when used to connect specific tools that have been collected as reference samples to be compared with forensic samples from the crime scene as physical evidence. Since most physical evidence that is seen at the crime scene involving criminal cases that require Toolmark examinations can’t be easily transported from the actual crime scene to the storage facility, this audio will describe, through pictures on the power point presentation, the many scientific techniques that are used to reproduce the tool marks from the actual evidence and how they are preserved for Forensic Analysts to analyze back in the Forensic Laboratory.
By clicking on the appropriate box below, you will began to unscrew and pry open a wealth of knowledge that will allow you to better understand how Toolmark Examination can be valuable physical evidence in Forensic Science investigations.