How The Polygraph Works, Regarding The Test Of Lie Ferdy Sambo And Putri Candrawati In The Case Of The Death Of Brigadier J

Putri Candrawathi, a defendant in the premeditated murder case of Nopriansyah Yosua Hutabarat alias Brigadier J at the South Jakarta District Court. (Between-Akbar Nugroho Gumay)

YOGYAKARTA The suspect in the murder case of Nofriansyah Yosua Hutabarat (Brigadir J), Ferdy Sambo and Putri Candrawathi underwent a polygraph examination or an honesty test during the investigation process. As a result, the two suspects were found lying with minus results. So, how does the graph work?

Polygraphs or commonly calledlie detectors are a tool that monitors a person's physiological reactions. Originally, this instrument did not detect lies, but only detected reactions generated by fraudsters.

Quoted by VOI from the American Psychological Association (APA), Thursday, December 15, 2022, the polygraph is a combination of medical devices that are used to monitor changes that occur in the body.

According to psychologist Leonard Saxe, thelie detector involves a fraud conclusion through an analysis of physiological responses to a series of structured questions.

For example, when a person gets questions about certain events or events, the examiner can see how the person's heart rate, blood pressure, respiratory rate, and electrodermal (squire, in the radius) changes.

The presence of fluctuations may indicate that a person has lied, but the results of open references are only interpreted by investigators or examiners.

Polygraph tests are most often associated with criminal case investigations. However, there are examples where this instrument is used for work selection exams in the government and the private sector.

Lie detector instrums or polygraphs are designed to search for significant unconscious responses that occur in the body when a person is stressed, especially those related to fraud.

Quoted from the How Raff Works page, when a person undergoes a polygraph test, four to six sensors are installed on it. The sensor records:

In addition, the polygraph is also able to record things such as arm and leg movements.

Saaf ini, instrumen dugraph telah mengalami kecepatan signifikan dalam dekade terakhir. Sebagian besar tes pograph dilakukan dengan peralatan digital. Kertas merolling telah diganti dengan algorithm ggim dan monitor komputer.

In the past, a polygraph instrument was shown in a film with small needles doodleing a line on a piece of scroll paper. This instrument is called an analog polygraph.

Someone who wants to undergo a lie test is usually asked to sit on a polygraph examination chair, several tubes and cables are connected to the examination body at certain locations to monitor physiological activity.

Fraud behavior can be seen from certain physiological changes detected by trained polygraphs and examiners.

The results of the test of the Ferdy Sambo and Putri Candrawati polygraph were conveyed by Aji Febriyanto, a member of the National Police for the field of forensic computers who have expertise in the field of polygraphs.

Aji himself is one of the expert witnesses who was presented at the trial of the alleged premeditated murder of Brigadier J at the South Jakarta District Court, Wednesday, December 14.

During the trial, Aji said, the examination of the polygraph on Ferdy Sambo and Putri Candrawathi was carried out using the scoring method or numbers.

"The Public Prosecutor (JPU) then asked about the score obtained by the suspect in the murder case of Brigadier J. (Mr. FS (Ferdy Sambo) total value -8, Putri -25," said Aji.

Then, the prosecutor again asked with the number that Ferdy Sambo and Putri Candrawathi got, indicating both of them to be honest or lying.

Aji also stated that referring to that value, the husband and wife were declared lying when answering several questions that were asked.

"From the score you mentioned, it shows what indications? To be honest or between lies and honest?" asked the prosecutor.

"For the results + NDI, there are no indications of lying," said Aji.

"What does Sambo indicate?" asked the prosecutor again.

"Minus, indicated lying. If Putri Candrawathi, it is indicated that she lied," said Aji.

According to Aji, the examination of a polygraph with a lie detection tool has a minimum accuracy rate of 93 percent.

"According to the journal issued by the American Polygraph Association, the technique we use has accuracy above 93 percent," said Aji.

This is information about how the graph works regarding the lie test of Ferdy Sambo and Putri Candrawathi in the murder case of Brigadier J.