The identification and reliability of static and dynamic barefoot impression measurements: A systematic review

Footwear-to-feet examination and analysis: Comparing worn footwear to persons and human remains

Footwear-to-feet examination and analysis refers to the process of examining and analyzing footwear in regard to criminal matters. This examination and analysis has been done to include or exclude an individual as the wearer of the footwear in question and to help associate or disassociate human remains to footwear. This review of the subject describes its investigative applications, the research that underpins the process, and considers its legal admissibility. The process of footwear-to-feet examination and analysis is scientifically valid and has been widely accepted. As a result, law enforcement and forensic scientists should be aware of the use of this process to assist in criminal investigations.

Recovery via SfM photogrammetry of latent footprint impressions in carpet

Impression evidence retained in carpet is usually recovered, if at all, in two dimensions via a vertical photograph. Here, we show that recovery is also possible via SfM photogrammetry and this gives good quality results that allow digital measurements both in the x-y plane and by depth (z-axis). This study focuses on recovery from polypropylene carpets which are widespread due to their resistance to wear and low cost. We show how traces can be recovered using both SfM photogrammetry and conventional photography with illumination provided via a crime scene light source. Experiments show that traces are retained for considerable time periods if left undisturbed, in excess of four weeks, but are quickly lost in under 8 hours by subsequent footfall. A simple simulation shows how the movement of an individual can be determined from carpet traces and the value of 3D recovery is illustrated via a set of experiments conducted with barefoot traces. We draw attention to the fact that 3D models allow a more statistical-based approach to be taken to match bare footprints at crime scenes. SfM photogrammetry is shown to provide a useful compliment to existing techniques and therefore worthy of further experimentation and potentially operational use.

Application of non-contact scanning to forensic podiatry: A feasibility study

Foot impression evidence recovered from crime scenes can be available in the form of barefoot prints, sock-clad footprints, or as impressions within footwear. In some cases, suspects leave their footwear at the scene of the crime, and the insoles from the footwear can be important in linking a person to the footwear. The application of 3D data-collecting technology is becoming more and more popular within forensic science and has been used to recover footwear impression evidence. The present study is a feasibility study to discover if 3D data capturing devices can be applied to insoles; to capture the footprint impression for measurement using the Gunn method (a method used in forensic podiatry casework). Three different methods of data capture were conducted; Adobe Photoshop, MeshLab, and calipers used directly on the insole. Paired t-tests and Intraclass Correlation Coefficient (ICC) were conducted for all three data capture methods. Seven measurements used in this study were significantly different across all three methods. ICC scores were moderate to excellent for the Photoshop method, poor to good for the 3D method, and moderate to excellent for the Direct method.