Evaluation of Zar-Pro lifting strip fidelity in comparison to other blood fingerprint enhancement methods

Fingerprints in blood indicate a threshold of violence has been surpassed in crime scenarios - making the crime resolution more urgent. There exist multiple processes that enhance a blood fingerprint in its original position, or in-situ, with reliability so that an image can be obtained. However, blood fingerprint evidence that cannot directly be transported to a laboratory for further analysis, due to the size or mobility of the substrate, calls for portability. In 2010 Zar-Pro Fluorescent Blood Lifting Strips were patented by Jessica Zarate as a "fluorogenic method for lifting, enhancing, and preserving blood impression evidence". The lifted prints are also inherently fluorescent to further increase enhancement and contrast of the print. There are currently no studies comparing Zar-Pro results with the results of other laboratory enhancement methods. This experiment compared Zar-Pro to other non-portable and frequently used alternatives - blood peak absorption and Hungarian Red enhancement to determine if Zar-Pro gives better blood fingerprint enhancement results than other non-portable alternatives - ALS visualization and Hungarian Red enhancement. In this study, Zar-Pro methods produced more reliable and reproducible results over the Hungarian Red and blood peak absorption methods on white and black ceramic tile. From this study, one can also conclude that ALS peak absorption is better suited for the location of blood prints on a light-colored item of evidence, rather than an enhancement method of blood prints