One of the many elements of the contentious U.S. Senate confirmation hearings for Supreme Court nominee Brett Kavanaugh in the autumn of 2018 was the disclosure that the woman who had accused Kavanaugh of sexually assaulting her back in 1982, Dr. Christine Blasey Ford, had taken and passed a polygraph examination. This facet of the confirmation brouhaha prompted debates about whether Judge Kavanaugh should similarly subject himself to polygraph examination, and about the reliability of such tests in general. (Kavanaugh responded to a question about whether he would take such a test by saying that he would do whatever the Judiciary Committee asked him to do, while pointing out that polygraph examinations are inadmissible in federal court because they are "unreliable.")
One of the pieces of evidence enlisted in support of one side of those debates was a claim that Judge Kavanaugh had once supposedly ruled in a case that "polygraphs can be accepted as gospel by employers in making hiring decisions":
The case referred to here was Sack v. Department of Defense (2016), an appeal for which Kavanaugh wrote the opinion. However, Sack v. Department of Defense was not a case involving employers or the use of polygraph tests (except in a tangential sense), nor did it produce an opinion in which Judge Kavanaugh asserted that employers could take polygraph results "as gospel."
The underlying lawsuit was filed by Kathryn Sack, a Ph.D. student at the University of Virginia, who was appealing the Department of Defense's (DOD) denial of her Freedom of Information Act (FOIA) requests for various DOD reports about the government's use of polygraph examinations and related documents, which she wanted to use for her dissertation on polygraph bias.
In order to justify their denial of Sack's requests, the DOD had to show that the records and information sought by her were "compiled for law enforcement purposes" and that their production would "disclose techniques and procedures for law enforcement investigations" and reasonably "risk circumvention of the law" -- thereby meeting the standards of FOIA Exemption 7E.
The court sided with the DOD in denying Sack's FOIA requests, holding that FOIA Exemption 7E should apply.
In Kavanaugh's opinion for the court, he noted that "the reports about polygraph use were compiled for law enforcement purposes," because law enforcement agencies use them for functions such as "test[ing] the credibility of witnesses and criminal defendants" and "screen[ing] applicants for security clearances," and therefore "the reports help ensure that law enforcement officers optimally use an important law enforcement tool." Kavanaugh also noted that the reports requested by Sack “identify deficiencies in law enforcement agencies’ polygraph programs,” and therefore releasing those reports could allow criminal suspects and others “to subvert polygraph examinations.”
Nothing in Judge Kavanaugh's opinion addressed whether "polygraphs can be accepted as gospel by employers in making hiring decisions." He merely observed, for the purposes of a very specific legal ruling, that the federal government sometimes uses polygraph tests for the purposes of screening applicants; he offered no judgment or opinion about their reliability or how they should or could be regarded by employers.