Gerald M Laporte

Learn More
Developing and implementing a generally accepted procedure for the dating of ink found on documents using dynamic approaches has been a very formidable undertaking by forensic document examiners. 2-Phenoxyethanol (PE), a common volatile organic compound found in ballpoint inks, has been recognized for over a decade as a solvent that evaporates as ink ages.(More)
A novel approach for the analysis of inkjet inks is being reported. A time-of-flight mass spectrometer, coupled with a Direct Analysis in Real Time (DART™) ion source (AccuTOF™ DART™), was used to determine if inkjet inks from various manufacturers and models of printers could be reliably differentiated, characterized, and identified. A total of 217 ink(More)
The submission to forensic laboratories of unknown specimens suspected of being biological or chemical warfare agents has increased tremendously with the threat of terrorism. Oftentimes, a threatening correspondence that contains hoax materials is intended to make the recipient(s) believe they have been exposed to a toxin. In some cases, the perpetrator can(More)
Gel ink pens have become a common writing instrument in the United States. Questioned document examiners often attempt to optically differentiate gel inks from each other and from other non-ballpoint ink writings (e.g., those from roller-ball pens). Since early formulations were primarily pigment-based, they do not elute when analyzed by thin-layer(More)
Utilizing a database of standards for forensic casework is a valuable resource. Undoubtedly, as more standards (and corresponding information about the specimens) are collected, there is a greater certainty of identification when a questioned and a known item cannot be distinguished after a series of analyses. The United States Secret Service and the(More)
Counterfeiting of currency and identity documents, death threats, illegitimate business transactions, and terrorist-related activities are some examples of the types of crimes that often involve documents produced from printers and copiers. Although standard protocol typically requires a questioned document (QD) examination prior to latent print (LP)(More)
Thin layer chromatography (TLC) is a scientific methodology that can be used to compare and characterize ink formulations. Occasionally, when evaluating chromatographic profiles on a TLC plate with ambient light, different ink formulations, or the same inks from different batches, may appear indistinguishable. The use of filtered light can be very effective(More)
The market is inundated with inkjet printers, laser printers, and photocopiers, which are often used in criminal activities. Many of these office machines are built by various manufacturers, hence they are constructed with different hardware designs (e.g. "rolling" and "grabbing" mechanisms) that have changed over the years due to technological advances.(More)