AFTE Store - An Evaluation of Various Griess and Modified Griess Test Protocols

This article examines various protocols and test media used for the Griess test as well as the Modified Griess test and compares the results obtained from each. The Modified Griess protocol and test media as written by John Dillon and taught by the FBI was compared to the alternate protocols in the FBI GSR Manual as well as those used by other agencies in terms of ease of use, quality of results, and cost. Also, the ease of use and quality of results obtained with the Griess test was compared to that of the Modified Griess test. The observations made by the author are that the Griess test has distinct advantages over the Modified Griess test in terms of visibility and increased contrast of point reactions against the background. Certain protocols and test material also had distinct advantages over others. Those found to be superior include the use of desensitized photographic paper as taught by the FBI as well as a technique developed and used by Robert Shem.