Toolmarks

Now that we know how firearms work, the next thing to look at are toolmarks and how these are created and examined.

The approach taken in the examination of toolmarks is essentially the same approach taken when examining the marks on bullets or cartridge cases made when they are fired, and which are used when attempting to link them to each other or to a weapon that may have fired them.

The video also discusses two very important concepts which are class characteristics and individual characteristics, and how these are used in the comparison of toolmarks to provide information in a forensic context.

You will also get some information about casting toolmarks using different techniques.

NB: The text and narration refer to something called a macroscope. This is not an error! These are low power mono or stereo magnifiers – typically in the 15 to 40X range – and are very useful in some toolmark examinations. For example, the detail in a tyre tread or footwear impression is often too fine to be clearly seen with the naked eye but too large for microscopy.