Friedrich H Lux*
Tire Global Information, Austria
Received date: September 02, 2013; Accepted date: September 18, 2013; Published date: September 23, 2013
Citation: Lux FH (2013) Tire Track Identification. J Forensic Res 4:198. doi:10.4172/2157-7145.1000198
Copyright: © 2013 Lux FH. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Visit for more related articles at Journal of Forensic Research
“Each tire on the street is unique ... that is the strategy of our business”
The identification of tire tracks at crime scenes has become very popular during the last 20 years. A positive identification of a specific tire pattern and the car of the suspects are very difficult because of our global tire and car market. With the help of modern IT equipment it will be more efficient for the investigators of forensic tire impression to analyze crime scenes [1-4].
Our product, a worldwide car and tire database, is focused on the Worlds market. That is necessary because approximately 60% of tires in the replacement market of the United States are imported from Europe and Asia. For easy use we decided to use a standard database format: Excel© and/or Access©.
The target of our database is mainly the identification of tire patterns, but they can also be used for copyright violation, mainly by Asian companies, and information on the import and export market of tires.
The foundations of each crime scene examination by our software are photographs or castings [1,5], including measurements from the pattern found (reference scales). The pattern can be taken from almost any surface. Mainly there are tire tracks on solid ground, sand, snow or mud, but we also have Figures of patterns on the skin of a person, imprints on the inside of trousers and objects lying on the street which were driven over by the car.
The first step is to classify specific properties of the pattern. The 7 classification criteria are: Vehicle type, pattern type, structure, center of the tire, circumferential groove near the centerline, characteristic of main blocks and shapes of main fine cuts.
Normally you will get between 1 and 15.000 results. In that case (normally up to 10 results) you have to manually compare the Figure from the crime scene to the photos in our database.
For further information on the specific footprint you have to know some technical details of cars, tires and a basic knowledge in physics. Knowledge [2,6-9] of the influence on air pressure, irregular wear, load of car, regular wear based on millage and condition of shock absorbers can narrow your result.
For the identification of vehicle tire tracks at the crime scene, you can measure the wheel base and front and rear tracks. The quality of these measurements depends on the soil texture, the axle design of the car and its weight. Based on the tire size of the original equipment of the car at its delivery, other sizes are permitted on the replacement market.
In most criminal cases cars are involved. That is why it can be helpful to know more about the car and its tires quickly. Our databases of cars and tires are a useful resource for crime scene investigators to find specific cars and tires at a crime scene.
There are 2 main fields in identification:
• Identification of tire pattern
• Identification of a car by its track on the ground
Tire book (manual search): The tire book is a list of about 5,000 different tire patterns from all over the world in the following categories:
* Passenger car tires (new and retread pattern)
* SUV and light truck tires (new and retread pattern)
* Agricultural tires
* Industrial tires
Tire Figures will be given by the industry in different resolutions and qualities. The patterns are sorted by type (see list above) and company. Tires older than 10 years are taken out due to the quantity (limitation: 400 printed pages with about 8000 Figures). A short technical description is included (Figure 2).
The correspondence to the Figure from the crime scene must be done manually.
Tire database (Electronic Search): The 2013 database contains 15,838 tire patterns from 357 different tire companies worldwide
The data in the database is the same as in the book, but there are the differences in:
• Quantity : no tire will be taken out (present: 15,000 pattern)
• Including motorcycle tires
• Searching criteria on tire name and/or producing company
• Searching criteria on pattern characteristic
• Vehicle type (e.g. passenger tire)
• Pattern characteristic (e.g. directional pattern)
• Structure of tire pattern (e.g. snow tire)
• Center of the tire (e.g. groove)
• Circumferential grooves at the center (e.g. straight groove)
• Shape of blocks (e.g. V-Shape - letter design)
• Shape of fine cuts inside the blocks (e.g. curved)
An electronic manual is added to the database. There you will find detailed instruction for using the filter functions.
As a result you will get 1 or more goals for your search. In Figure 3 (bottom, left) you will see the result in the Access version.
The results of Access and Excel version are equal. It is subject to the user which program they want to use (Figure 4).
The 2013 database contains 12,706 different car models from 191 car producers worldwide.
The database is written in excel format. Based on car producers and model, front and rear track and wheelbase are listed (Figure 5). The given tire size is the original equipment which is used on the new car. This tire size should be the same for the delivery in every country. It is known that some countries use a replacement tire size.
Figure 6 shows a front or rear track on a paved road. On unpaved roads you will normally find front and rear track including the wheel base. Depending on the axle geometry you can sometimes decide if the car was used under full load. In one crime case, some years ago, it was important to know, if the stolen car was still under load.
The Excel database in Figure 7 is listed in [mm] and [inch]. In column K you will find the typical original equipment tire size.
For the replacement market there is a separate database to find equivalent tire sizes. Regarding to law you should use the same diameter of tires. If somebody does not use the diameter of the original tire size, it is nearly impossible to find the corresponding car.
Figure 8 shows the main menu (a pdf file with links) of our “Database Library”. Each button will open an Excel or Access file or the “tire book” in pdf format. A link to our website <http://www.tgi.co.at> and mail address <[email protected]> is included.
Content of database library
*Top left: 3 different versions of the car database (book, excel and access)
* Top center: car database
* Top right: conversion table for replacement tire sizes (Figure 9)
* Center left: database for speed and load index (Figures 10 and 11)
* Center, below car database: DOT codes for the production location of each tire and the UTQG code for “traction, wear and temperature” which are important for the use of tires
* All other databases are addresses of tire companies, old timer’s tire dealers
To find a car or tire involved in a crime it is easy to use the databases to get preliminary results. No database will replace person evaluating the results. The aim of our databases is to reduce time for the crime scene team in order to get an overview of relevant tire tracks and start the search for the involved vehicles.
The database is written in standard Microsoft format “Excel” and “Access” so that it can be used worldwide.