Examination Of The Duration Of Immersion In Water And Extent Of Pruning Observed On Fingertips

Abstract

In the realm of forensic science, fingers are normally thought of as evidence for identification; however, it is imperative that the forensic science community understands other valuable evidence that fingers can provide in aquatic medicolegal death investigations and criminal nonfatal investigations. This research project examined the development of fingertip pruning during 120 minutes of immersion in warm tap water that was allowed to cool, instead of being held constant. Additionally, this research examined the dissipation of fingertip pruning for 60 minutes after removal from the water. This research utilized ImageJ, an image analysis software, to provide two measures of quantitative results: the amount of swelling of individual friction ridges at each time interval and the percentage of the overall fingertip surface area with visible pruning. The findings of this study indicated that friction ridges increased in width as the duration of immersion increased, with some variation. Additionally, the percentage of surface area covered by pruning had a strong correlation between duration of immersion in water and duration of time removed from water. Lastly, the changes in the fingertip condition occurred quickly, within 20 minutes, and even after two hours of water immersion, the most obvious presence of pruning dissipated within 30 minutes; this supported that fingertip pruning should be treated as transient evidence in aquatic criminal investigations.