Laterally Reversed Fingerprints Detected in Fake Documents

Cases involving laterally reversed fingerprints have been previously reported in the literature. In general, they are detected only when the expert already has suspects and is able to analyze the latent prints' substrate. This case is about the analysis of hundreds of copies of supposedly fake identity documents in which reversed fingerprints were detected, not from characteristics of the substrate, but because of the attention paid by experienced experts during all stages of their work. Some difficulties associated with the detection of laterally reversed fingerprints are discussed in terms of visual percep- tion, contextual bias, operational procedures, automated fingerprint identification system (AFIS), and accuracy of decision making based on costs and benefits. Possible solutions for avoiding errors when dealing with probable lateral reversals are discussed: (1) applying the ACE-V methodology with blind verification and (2) in specific circum- stances, performing comparisons with both direct and reversed prints and storing them in AFIS (if possible) to allow for future comparisons.