A controlled experiment involving human behavior doesn't yield valid results if its subjects know they're participating in an experiment or if their environment is manipulated for the purpose of an experiment.It happens that some behavioral psychologists are conducting laboratory studies to see if liars can be detected by their behavior. Critics of those experiments make this point:
Some researchers think...that the design of the laboratory studies is responsible for the poor rates of lie detection. "People are very good liars when nothing is at stake," says Aldert Vrij of the University of Portsmouth in England. "But a lab setting is not real life."Exactly!
In most experiments, researchers tell the subjects whether or not to lie, and the lies have no effect on their lives. There's no significant reward for a liar who's believed or punishment for a judge who's duped.
"There is definitely a lack of real-life stuff in this field of research," says Vrij.