CLPEX Chat Board

Our agency is researching the Electrostatic Dust Lifter and I would like some input from those that use same. Over the years we have used Gel Lifts and have had great results. Just recently our agency assisted another with processing a robbery crime scene. This agency did have a EDL available but I noticed they were pleased with our gel lifts. So before I shell out the money for this item do those that have this item use it? Do you believe using gel lifts, photograph with side lights, etc is just as effective. I would rather know all I can , rather than purchase an item that becomes a paperweight. Do you suggest I just purchase other materials and/or supplies?

Thanks to those who respond.
RMorris, Sgt

Well, while they both do well in the recovery of marks as result of dust transfer to a suitable substrate, they do have differences. An advantage of DLK/ESDA technique is in ‘blind search’ examinations. Electrostatic applications can recover marks not readily seen by the naked eye, but which may be present on items such as papers found strewed at crime scenes. There is nothing lost or damaged by using a DLK or ESDA device and the results can be very surprising and yield very valuable evidence. DLK’s can also be used to process large surface areas in blind search applications, while gel lifters are limited in size.

I wrote an article in 1993 (JFI, 43:4, 1993) about using an ESDA device on paper evidence that still borne visible footwear tracks in a 13-year old case. The tracks had only been photographed at the time of original examination and then stored away in the case file. I was curious about an additional examination by ESDA. As explained in the article, the ESDA recovered tracks were greatly enhanced over the photographs taken 13 years earlier and being stored for all those years. However, something I never did write about was that a few years later when gel lifters came into vogue, I got curious again and processed the paper once again with gel lifters. The results were an improvement over the ESDA recovered tracks, but did remove much as the deposited residue. I have often wondered if the hydraulic press technique developed by Israeli police for gel lifters (Journal of Forensic Sciences, 42:2, 2003) would be able to eke out the tracks once more even when residue was no longer visible.

ESDA/DLK devices are better for processing large surface areas, can be used in blind search techniques and work very well with very faint traces. Gel lifters are also very good with the recovery of very faint traces, but are not practical for blind searches and are limited by the size of the lifter. While the financial outlay for a DLK device may be somewhat substantial, the device will probably never wear out and the lifting mylar can be used many times (the mylar film does have limitations depend on its care and other factors). The financial outlay for gel lifters can also be substantial and they should not be re-used. If you have the resources, have both at your disposal and evaluate which to use (perhaps both) under the circumstances.

I just submitted a paper to the JFI on some research I did with other footwear examiners on a new product known as static cling film. It's not really a new product, but it's a new application. This is the vinyl film which clings to smooth surfaces and is used as advertising on the sides of cars, buses, etc. It is available in 9" x 14" sheets for less than one dollar a sheet. In our study it proved to be as effective if not more than ESDL. It costs a lot less, is really easy to use and is a lot more cost effective than ESDL or gel lifters.

We order it from Grafix Plastics, 800-447-2349. Black Opaque Static Cling. 9" x 14". $0.97 per sheet for 500 sheets.

Keep an eye out for the paper in the JFI.