The Research, Development, Training and Education (RDT&E) Interagency Working Group (IWG) was tasked by the Subcommittee on Forensic Science to identify current and future plans for research, development, testing and evaluation related to forensic science and conduct gap analysis in the forensic science disciplines. As a result, the IWG requested SWGTREAD present information highlighting the scientific basis of shoeprint and tire tread analysis and how the discipline meets Daubert criteria. This presentation was made on May 11, 2011.
Based on the information presented, 15 questions were generated by the IWG to assist them with their mission. On August 22, 2011, the IWG contacted SWGTREAD to provide the opportunity to submit the appropriate literature references for each question. The IWG stated that this information will generate a better understanding of the existing research related to shoeprint and tire tread analysis.
The following questions were provided to SWGTREAD.
- What literature exists that addresses the number of characteristics/identifying marks required to render a conclusion?
- What is the literature that discusses the use of statistics to support an examiner’s conclusion?
- What literature exists that measures the consistency of examiner conclusions, incorporating multiple examiners, with various training and experience, given the same sample set of known “matches” and known “non-matches” of varying quality?
- What is the literature that addresses the effects of examiner experience/training/caseload in shoeprint/tire tread examinations?
- What is the literature on the potential and actual cognitive bias in shoeprint and tire tread examinations?
- What literature exists that investigates the effects of environmental conditions on shoeprint/tire treads? What is the literature that documents the formation of individual characteristics amongst a group of people wearing the same shoe for the same period of time?
- What is the literature that investigates the transfer of indentifying features from sole or tread to impression medium across differing substrates?
- What is the literature that investigates the development of defects/individualizing characteristics on different sole or tread materials?
- What literature exists that describes the automated systems in shoeprint/tire tread examinations? What literature exists that addresses the accuracy and validity of automated systems in shoeprint/tire tread examinations? What literature exists that addresses the effectiveness of human examiners and automated systems used in conjunction to render a conclusion in shoeprint/tire tread examinations?
- What is the literature on error rates in shoeprint/tire tread examinations?
- What is the literature that addresses the feasibility and reliability of partial print comparisons (i.e. situations where some of the sole pattern may be present with individual detail, but there is insufficient detail to compare class characteristics)?
- What is the literature that describes the rarity of class characteristics and uniqueness of individual characteristics in shoeprints/tire treads? What published databases exist that describe the frequency statistics of various shoeprint/tire tread patterns?
- What is the literature on quantification; measurement precision and uncertainty in shoeprint/tire tread examinations? For example, are there studies that would help describe “small” and “large” scratches in terms of measurement uncertainty? For example, is > 1.0 cm plus/minus 0.1cm big and how jagged does a scratch need to be before it is unique?
- What is the literature on population-based studies that describe variation (e.g. due to gender, pathologies, height/weight, running vs. walking, stride, etc)?
- What new technologies and areas of research should be pursued with regard to shoeprint and tire tread examination and analysis—and in what priority? (Note- this does not require a list of references, it is for informational purposes only.)