DescriptionThe fingerprint enhancement techniques used must be safe and simple for the analysts. In the forensic science field several chemical agents are used for the enhancement of fingerprints in blood. However, there are advantages and disadvantages in the use of chemical enhancing agents. In this study, lac dye is used to enhance bloody fingerprints on three porous surfaces (cellulose paper, thermal paper and cotton paper). Three different lac dye concentrations (0.1%, 0.25%, 0.5%) were made for enhancing the fingerprints in blood. Bloody fingerprints were made using a depletion series to see the efficiency of the lac dye concentrations. The enhanced fingerprint was evaluated by the contrast of the fingerprint from the background, the visibility of minutiae and the number of minutiae found. The results revealed that 0.5% lac dye stain was efficient in enhancing the finger marks in blood on all the three porous surfaces used. 0.25% lac dye stain was the minimum concentration required for the visibility of bloody fingerprints in porous surfaces. Further studies on the lac dye efficiency on porous surfaces can be done by comparing it with a widely used enhancer like amido black. Studies using lac dye on other porous surfaces like fabrics, plywood, etc., is also recommended.