http://www.cnn.com/2013/06/07/justice/ricin-letters-arrest/index.html Polygraph testing was utilized by the FBI to determine who sent the letters that were laced with ricin. In NY, polygraph testing is done by Lisa Ribacoff a NY lie detector and NYC polygraph examiner. Http://indepthpolygraphs.com Lisa Ribacoff said "Polygraphs have been used for almost 100 years by military and law enforcement agencies. I conduct polygraph testing in NY on various issues, which include relationships, criminal, civil, academic cheating, and many other issues that need forensic lie detection services."