One day after Republican Sen. Lindsey Graham, R-S.C., raised concerns about the polygraph test taken by Brett Kavanaugh accuser Christine Ford, her attorney is refusing to comment on who paid for the examination or provide additional details on how it was conducted.

And experts contacted by Fox News confirmed that while polygraph examinations can be useful, they are ultimately fallible tools that "can be beaten." Without mentioning any particular instances, one former senior FBI agent said polygraphs would have difficulty detecting deception by sociopaths, psychopaths and committed liars lacking a "conscience."

Even well-intentioned individuals who have come to believe that their false stories are, in fact, true -- whether because of therapist-induced memories or other causes -- can sometimes pass polygraph tests, former FBI officials and psychology experts told Fox News.

Ford provided The Washington Post the results of a polygraph examination conducted by a former FBI agent in August, which reportedly showed that she had been truthful in her allegations. According to the Post, Ford took the polygraph on the advice of her attorney, Debra Katz.

Katz did not respond to numerous requests for comment by Fox News on Tuesday concerning the polygraph.

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Speaking to Fox News' "Hannity" on Monday, Graham questioned who had paid for the polygraph, which experts told Fox News could cost anywhere from $500 to $1,000.

"If Ms. Ford really did not want to come forward, never intended to come forward ... why did she pay for a polygraph in August, and why did she hire a lawyer in August? And who paid for it?" Graham asked.

Democratic politicians and operatives have repeatedly cited the claim that Ford had passed a polygraph exam to bolster her claims.

"The woman who says Kavanaugh attacked her has reportedly passed a polygraph test," Paul Begala, a onetime aide to former President Bill Clinton while he was besieged by numerous accusations of sexual misconduct while in office. "Will Kavanaugh take one?"

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But several experts told Fox News that viewing polygraphs as reliable lie-detector machines is a dangerous oversimplification.

"If someone is a psychopath or a sociopath, if you don't have a conscience ... you can beat it." — Former FBI agent James Gagliano

"It's not the result of the polygraph; it is what polygraph subjects say during the polygraph interview that is most valuable," said Thomas Mauriello, a lecturer in criminology at the University of Maryland who worked as a senior polygraph examiner at the Defense Department.

"The result of a polygraph simply is whether you did or did not respond to a particular question. A response is not a lie, because the polygraph is not a lie detector as most think," Mauriello added. "A response is the activation of your sympathetic nervous system when answering a question asked during the examination."

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James Gagliano, a former FBI agent who led a SWAT team in New York for several years and now teaches at St. John's University, told Fox News that while polygraphs are valuable, they "can be beaten."

"In this case, if they want to put this out as irrefutable evidence that this woman is telling the truth because she passed a polygraph -- that's not the way polygraphs work," Gagliano added. "If that were the case, I would've taken every drug dealer, gangbanger, and pedophile I investigated, and I would've thrown them on the polygraph."

Gagliano, who said he was subjected to several polygraphs at the FBI but never administered one himself, said people can sometimes pass polygraphs if they've convinced themselves they are telling the truth: "It's not a lie if you believe it," he said.

"Everyone knows polygraph exams can be beaten," Gagliano added. "If someone is a psychopath or a sociopath, if you don't have a conscience, if you don't know right from wrong -- you can beat it."



Ford announced on Tuesday she would refuse to testify about her allegations, despite numerous invitations from Senate Republicans, until the FBI conducts a full investigation into the events she claims occurred at a house in Maryland more than 35 years ago. Ford has been unable to identify who owned the house in question, or why she was there.

"It's totally inappropriate for someone to demand we use law enforcement resources to investigate a 35-year-old allegation when she won't go under oath and can't remember key details including when or where it happened," a federal law enforcement official told Fox News.

Gagliano explained that polygraphs are typically conducted by highly trained professionals who first establish a "baseline" physiological response by asking simplistic questions. Then, Gagliano said, polygraphists often attempt to "scare" examinees by asking a question to make them think they're in trouble, which provides an additional data point.

Speaking separately on "The Ingraham Angle" Monday night, Mauriello explained that numerous factors -- including how questioners pose those complicated interrogatories -- can affect polygraph results.

Asked what it meant that Ford had passed a polygraph, Mauriello said flatly, "absolutely nothing."

Sen. Dianne Feinstein, D-Calif., the ranking Democrat on the Judiciary Committee, seemed to admit as much Tuesday night, even as she insisted Ford was credible.

"This is a woman who has been profoundly impacted by this," Feinstein told Fox News. "Now, I can't say everything's truthful. I don't know."