In regard to the ability of people unable to speak a language to detect lying, this may be a result not of their inability to speak or understand any language but merely their inability to speak or understand the language the speakers were using. Some years ago, while visiting Japan, I saw a television show there obviously modeled on the U.S. show To Tell the Truth, with three people claiming to be a particular person. Back home, I guessed the right person a bit more often than chance would allow. But watching the Japanese show, when I knew only a few words of Japanese and had to depend on tone of voice and body language, I was right nearly all the time. I don’t know if I’m typical, but this looks like a promising course for further research.
Los Angeles, Calif.