Voice-stress analysis, an alternative to the polygraph as a method for lie detection, is already widely used in police and insurance fraud investigations. Now, however, it is being touted as a powerful and effective tool for an array of new applications -- everything from the screening of potential terrorists in the nation's airports to catching wayward spouses in messy marital disputes. Despite its booming popularity, a number of federally sponsored studies have found little or no scientific evidence to support the notion that existing voice-stress technologies are capable of consistently detecting lies and deceptions.