Reliability of paper brightness in authenticating documents

Evaluation of paper brightness in multipage documents is a practice of forensic document examiners when there is a question of a page insertion or substitution. This article demonstrates that occasional errors occur in the manufacturing process that affects the consistency of paper brightness. The inconsistency of paper brightness may therefore influence conclusions reached in authenticating documents. Reams of multipurpose paper, from 21 manufacturers, were examined. When assessing the individual pages of each package with an ultraviolet light, approximately 30% of the reams revealed differences in paper brightness. A study of the paper-manufacturing process was conducted to determine where variations originate. It is concluded that brightness differences occur when one incompatible roll of paper is mistakenly placed with others used for one production run. It was also determined that brightness variations (when present) are patterned throughout individual reams. When the authenticity of a document is in question, consideration of these findings is essential to assure an accurate assessment.