"Different sorts of polygraph examinations have been conducted in Poland over the last sixty years (Krzyścin, 226, 227). It is curious that there are few empirical studies which concern the accuracy of such examinations in relation to the population of Poland. Hundreds of well-documented scientific studies on the accuracy of polygraph examination have been published all over the world. However, most concentrate on the American or Israeli population, so the problem of national differences should be taken into consideration, too. "(...)