questioned-document analysis

Questioned-document analysis is a branch of forensic science focused on examining documents to answer questions about their origin, authenticity, or alteration. This field helps identify handwriting and typewriting, determine a document's age, and reconstruct the sequence of events related to its creation or modification.1

Forensic document examiners use various techniques. Handwriting analysis is based on the principle that adult writing develops unique characteristics. Forged signatures can be identified, though careful tracings can sometimes be difficult to attribute to a specific forger. Historically, investigators also examined typewriters and compared inks using chemical tests. Paper can be differentiated by its fiber, filler, and sizing constituents, analyzed through staining, microscopic examination, X-ray diffraction, and chemical tests. This meticulous examination of physical evidence is crucial in legal proceedings.12