Age estimation of bloodstained fingermarks

Bloodstains and fingermarks discovered at crime scenes can provide crucial information to an investigation. A DNA profile can be obtained from a bloodstain and can be used to link someone to a crime scene, corroborating or disputing a witnesses' statement. Besides DNA evidence, fingermark analysis is another common method that is also used to identify an individual. However, analysis of neither bloodstains nor fingermarks is able to answer a key question for investigators: how much time has passed since the criminal event occurred? Determining the time since deposition (TSD) of bloodstained fingermarks could be important for crime scene investigators. If crime scenes contain multiple sets of bloodstains, TSD determined for individual bloodstains should allow for selecting bloodstains relevant to the crime and as such reduce the number of samples which are collected and processed. Despite the extensive research conducted over the last century, there is still no definitive answer on how to determine the TSD of blood. This chapter summarizes the work that has been done thus far to tackle this momentous issue. However, there are still hurdles that must be overcome before methods for estimating TSD of bloodstained fingermarks become accepted by the judiciary in the court system.