Whenever a document is used during the commission of a crime, the follow-up investigation is often the critical issue in determining the authenticity of a questioned document in resolving a dispute or criminal matter.
Authenticating a questioned document can include anything written, printed, typed, or reproduced, such as checks, contracts, wills, letters, threatening and anonymous notes, robbery notes, and counterfeit documents. Identity theft crimes that are committed with documents are also a growing trend. At the Idaho State Police, the following forensic document examination services are available to all client agencies in the state:
- Handwriting examinations determine the authorship question of written content and signatures. Evidence items submitted for handwriting examinations and comparisons might identify an individual writer or determine that the individual did not author the questioned document. The investigator must collect sufficient questions and known documents suitable in quality and quantity for a meaningful examination and comparison. Investigators can obtain known writing samples from the requested standards and the collected standards. Requested standards are those known writing samples in which the investigator administers and witnesses the subject providing the known writing. Collected standards are those known writing samples that the court has accepted as being the genuine known writing of the subject.
- Printing process examinations determine how a document was created and by what process. Whether the questioned document submitted for examination was printed on a multifunction printer, a typewriter, a photocopier, or a commercial process, valuable information about the printing process used to prepare the questioned document may be revealed. This is important for counterfeiting cases involving car titles, checks, certificates, and government-issued ID cards.
- Indented document examinations detect and visualize latent indented writing or markings and may determine the source of a questioned document. Latent indented writing and other valuable markings can appear on the sheet(s) below a source document. A pad of paper is a good example of how indented writing is created by the transfer of pressure from a writing instrument from the page of writing to the pages underneath. This type of examination during the investigation of anonymous letter and note cases may provide the investigator with helpful information. Careful packaging of this type of document evidence by the investigator is crucial from collection to submission to the laboratory to prevent unintended impressions on the evidence items.
- Physical match examinations associate torn or cut documents with a source document. Careful examination techniques are employed to preserve this delicate evidence, such as associating torn pages with a source tablet or notebook. Examination of a shredded document for restoration may also yield helpful information to the investigator.
- Non-destructive ink and paper examinations determine, depending on the submission, whether ink or paper samples can be distinguished from other respected samples. Examinations of this nature are often used in cases suspected of involving altered or counterfeit documents.
- Charred and liquid-soaked document examinations restore damaged documents for investigative purposes. Careful handling and examination techniques are employed to preserve this delicate evidence. Cautious handling of this type of document evidence by the investigator is crucial from the collection, packaging, and submission to the laboratory. The agency is encouraged to consult with the laboratory before submitting to it.