How can a document be tested for manipulation in CSI?
Manipulation implies irrations and alterations and obliterations. Normally, various photographic techniques, such as uv photography or infra red photography are employed to extract information from those type of documents. Another interesting approach would be in a device know as the ESDA (electrostatic detection apparatus)which is used to determine or detect the presence of indented writings on documents, and that is another rather sophisticated technique that is used in addition to photography.