Criminal Investigation Week 6
Footwear and Tire Impressions

Quiz on reading.

Lecture.  Week 6. 

    Shoe and tire impressions may be the most overlooked evidence commonly available at crime scenes.  These impressions are not difficult to recover, but the task is time consuming and can be messy.

    First, a little terminology.

     Class characteristics are the general "look" of a particular style of shoe as it was produced by the factory.  By ascertaining the class characteristic, we can say that a particular shoeprint was made by a particular model of shoe, say a Nike model 6401 shoe.  This narrows the field of possible shoes from all the shoes in the world to however many Nike model 6401's were made.  Not great, but better than all the shoes in the world.  Recall that in the O.J. Simpson murder trial, the prosecution put on evidence that a shoeprint found at the murder scene was made by a size 12 Bruno Magli shoe, which were rather rare.

     Individual characteristics are those that come from wear and use.  Cuts in the sole from rocks or sharp objects, wear on the tread from a certain walking style, and broken tread are all individual characteristics that can confirm or eliminate a particular unknown impression from the crime scene.  Because these marks are random, the individual characteristics can narrow the field of all Nike model 6401 shoes toa particular known Nike model 6401 shoe that has been recovered and is being examined.

    TO BE CONTINUED.  FOR NOW, SEE READING ASSIGNMENT BELOW.


   

Reading Assignment for THIS week: 

           Footware and Tire Impression Evidence

           Practical Example of Footware Evidence

           Plaster Casting Techniques

Back to Crimininal Investigation


Christopher Bruno