While polygraph operators may be "true believers," there is broad consensus amongst scientists that polygraph testing has no scientific basis. The LAPD polygraph unit is wrongly branding as liars many qualified, honest applicants. On the other hand, liars can fool the polygraph using simple countermeasures that polygraphers have no demonstrated ability to detect. The criticisms I raised in my 2001 Daily News op-ed piece, "LAPD Polygraph Test Results Don't Tell Full Truth" remain valid today:

http://antipolygraph.org/articles/article-033.shtml

In 2004, AntiPolygraph.org received seemingly credible allegations that the then supervisor of the LAPD polygraph unit had secretly altered the results of dozens of polygraph examinations. The LAPD refused to provide documentation of an investigation into the allegations when AntiPolygraph.org requested it under the California Public Records Act:

https://antipolygraph.org/cgi-bin/forums/YaBB.pl?num=1081980240

More recently, we've received a report that the supervisor in question has been quietly removed from the polygraph unit:

https://antipolygraph.org/cgi-bin/forums/YaBB.pl?num=1182068515

In a landmark report published in 2002, the National Academy of Sciences concluded that "[polygraph testing's] accuracy in distinguishing actual or potential security violators from innocent test takers is insufficient to justify reliance on its use in employee security screening in federal agencies." The goes for the LAPD, which should terminate its misplaced reliance on this junk science.