Experiment 21. Glass Fractures and Direction of Force
A large portion of the casework performed by forensic document examiners involves the identification of authorship of handwritten documents such as historical records, letters, wills, currency, robbery notes, and checks. Often, document examiners are called upon to determine if a document has been altered, such as overwriting of a check amount or changing a signature on a will. A simple, yet effective way to detect such alterations is with thin-layer chromatography (TLC).