For at least the second time since 2012, the federal government has brought criminal charges, accusing someone of training people on how to beat a polygraph test. On Friday, prosecutors announced an indictment against Douglas G. Williams, a 69-year-old man from Norman, Okla., who’s accused of coaching people “how to lie and conceal crimes” during federally administered lie-detector tests. Mr. Williams, who operates a company called Polygraph.com, says the mail fraud and obstruction of justice charges leveled against him are an “attack on his First Amendment rights.” The indictment follows the federal prosecution of an Indiana man who received eight...