{{Short description|Analysis of tire treads at crime scenes}} {{ForensicScience}} '''Forensic tire tread evidence''' records and analyzes impressions of vehicle tire treads for use in legal proceedings to help place a suspect at a crime scene<ref name=":2">{{Cite web |title=Tire Tracks |url=https://www.crimemuseum.org/crime-library/forensic-investigation/tire-tracks/ |access-date=2026-03-03 |website=Crime Museum |language=en-US}}</ref>. Every tire will show different amounts of tread wear, and different amounts of damage in the form of tiny cuts, nicks, and scratches<ref name=":0">{{Cite report |url=https://www.justice.gov/archives/olp/file/861931/dl |title=Supporting Documentation for Department of Justice Proposed Uniform Language for Testimony and Reports for the Forensic Footwear and Tire Impression Discipline |publisher=U.S. Department of Justice |access-date=February 26, 2026 |department=Office of Legal Policy}}</ref>. These unique characteristics will also show on the impression left by the tire.
== History == This forensic technique was first invented in 1930 by David Chapman, a researcher affiliated with the Sheriff's Office in Los Angeles, California, in the United States<ref name=":1">{{citation | journal = Popular Science | title = Tire "Fingerprints" to Trace Bandit Cars | year = 1930 | volume = 116 | issue = 2 | issn = 0161-7370 | page = 61 | url = https://books.google.com/books?id=4ykDAAAAMBAJ}}</ref>. A try-square would be placed on the ground around the tire mark to measure it. It was difficult to identify the tire just from a photograph, so they used calculations based on the camera position and other data to identify it. With the calculations, they were able to find size, make, car type, load, mileage, and where the car was driven<ref name=":1" />. In the 1930s to the 1960s, FBI analysts expanded from 1800 patterns of tire tread to include dimensions and characteristics<ref name=":0" />.
== Prints == A visible print is something that can be seen with the naked eye. Examples would be muddy tracks on the ground or tire imprints in the snow<ref name=":2" /><ref name=":3">{{Cite web |title=Footwear & Tire Track Examination: How It’s Done |url=https://www.forensicsciencesimplified.org/fwtt/how.html |access-date=2026-03-05 |website=www.forensicsciencesimplified.org}}</ref>.
A plastic print is an impression left on a soft surface like mud or sand<ref name=":3" />. These can be 2-dimensional or 3-dimensional<ref name=":2" />.
A latent print is not visible to the naked eye without manipulation<ref name=":2" />. They are usually found on surfaces that are flat, like a sidewalk or a driveway. Static is used to make a print. Chemicals, powders, or alternative light are used to see a print already on the ground<ref name=":3" />.
== Ways to collect samples == Photography is a simple way to collect visible prints<ref name=":2" />.
Casting is the most common way to collect samples. This is when powdered stone material is mixed with water and poured into the impression to create a three-dimensional cast<ref name=":3" /><ref name=":2" />.
A thick coating of adhesive can be used on smooth, non-delicate surfaces. Rubber with a low-adhesive gelatin layer is what is used on rougher surfaces<ref name=":3" />.
An Electrostatic dust-print lifting device is used for prints that are dry or dusty. It charges the particles and attaches them to a lifting film like a gelatin lifter<ref name=":3" /><ref name=":2" />.
Chemicals, powders, or alternative light can also be used to enhance prints that have already been collected<ref name=":3" />.
Samples collected are compared side by side to prints from manufacturers to tell which marks were created by the crime and which are in the original design<ref name=":3" />.
==References== {{reflist}}
==External links== [https://research-ebsco-com.uncfsu.idm.oclc.org/c/47gpat/viewer/pdf/zy62s6f7w5?auth-callid=c6071f9d-dd2d-45b2-9881-98cdb26eb517 Vehicular Locard's principle and patterned tire markings. - EBSCO]
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{{Use mdy dates|date=September 2020}} Category:Tires Tire tread evidence
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