All of the decisions involved Guilty Knowledge Techniques, and all decisions regarding whether or not the subjects were deceptive were verified. In each situation, the deceptive admitted to the knowledge of the critical information in the test. Respiration amplitude during deception, compared to the pre-stimulus level, is suppressed. There was a significant increase of expiratory time demonstrated with the critical question, while changes of inspiration time were not significant. The rate of curve linear length (CLL) of respiratory tracing (CLL by cycle time) decreased significantly during critical question onset relating to noncritical questions. The rate of CLL to the noncritical question after the critical question was significantly more enhanced than the rate before the critical question. In conclusion, the increased cycle time during critical question onset depends on changes of the expiratory function of respiration and the increasing rate of CLL after the critical question associates with rebound components of suppression following deception. 5 figures, 1 table, and 19 references (Author abstract)