​A suspect's confession to committing an offense does not necessarily indicate that they actually committed the alleged act, even though it may create the impression that if they confessed, they must be guilty.​
In the past, a suspect's confession was commonly regarded as the "mother of all evidence." However, over time, as various cases emerged, the need arose to substantiate the suspect's guilt with additional evidence.

This raises the question: what motivates a false confession, and why might individuals admit to offenses they did not commit? Over the years, various cases have been reported in the Israeli media in which suspects allegedly confessed to acts they had not committed, due to significant and real pressure during their interrogation by the investigative team. These include the Amos Baranes case, the Ma'atz affair, and the murder case of Hanit Kikos, in which it was reported that the individual convicted of her murder had a personal development level lower than that of a six-year-old child, and it was ultimately revealed that the body was discovered in an entirely different location from the one he had indicated in his confession.

When examining a suspect's confession, significant weight is given to CIDs (Concealed Investigation Details) provided by the suspect during the confession. A Concealed Investigation Detail refers to specific information related to the committed offense, known only to the perpetrator and the investigative team, and which has not been disclosed to the media.
In many cases, the Concealed Investigation Details (CIDs) are first provided to the investigative team by the suspect themselves, such as the location of a hidden body or stolen property, the whereabouts of the murder weapon or burglary tools, and similar critical information.

In the conviction of Roman Zadorov in the murder trial of Tair Rada, Judge Cohen based the conviction on the fact that Zadorov knew at least seven concealed details that no one other than the murderer could have known, as well as on Zadorov’s confession to an undercover informant. The judge emphasized that the confession was not based on the informant’s testimony, but rather on Zadorov’s own recorded statements.

The Use of Concealed Investigation Details (CIDs) in Conducting Polygraph Examinations
Extensive research conducted in the field of polygraph examinations has found that the reliability of tests based on the CID (Concealed Investigation Details) method is significantly higher than that of tests based on the Control Question Technique (CQT). Therefore, it is of great importance that the investigative team refrains from disclosing CIDs to the suspects prior to conducting polygraph examinations.

In Japan, for example, most polygraph examinations are conducted using the Concealed Information Test (CIT) rather than the Control Question Technique (CQT). After a crime occurs, the crime scene is completely sealed off, and forensic investigators along with polygraph examiners arrive to identify Concealed Investigation Details (CIDs) related to the offense. Subsequently, polygraph examinations based on the CIT method are conducted to screen potential suspects.

There is a fundamental difference between the two main polygraph examination methods: In the Control Question Technique (CQT), the examinee’s physiological responses to different types of questions are compared. The comparison is made between the examinee’s responses to relevant questions concerning the investigation and to control questions, allowing the examiner to determine whether the examinee is telling the truth or lying. In contrast, the Concealed Information Test (CIT) examines whether the examinee recognizes specific Concealed Investigation Details (CIDs) presented during the examination. The underlying assumption is that a person involved in the incident, who is familiar with the concealed information, will exhibit a distinct physiological response when the relevant item is presented, differing from their responses to unrelated items — particularly when the concealed item is significant, such as a burglary tool or, in the case of Tair Rada, the weapon used in the murder. Conversely, an examinee with no connection to the incident would not recognize the concealed detail, and therefore would not display a differential physiological reaction when it is presented among other neutral items. The English name of this method is the Concealed Information Test (CIT), and it is commonly used when a suspect denies any connection to the investigated event and claims to have no knowledge of the incident or its details, while the investigators possess concealed information that can assist in the examination.

An example of a Concealed Investigation Detail (CID) familiar to many cinema enthusiasts can be found in the movie "The Silence of the Lambs." In the film, a forensic pathologist discovers a common trait among all the victims’ bodies: the killer had placed a cocoon of a rare butterfly species inside the throats of his victims — a unique "fingerprint" of the specific murderer. This detail was not disclosed to the media or made known to the public. However, according to the plot, it led to a major breakthrough in the murder investigation and the eventual identification of the serial killer, who, among other things, bred that rare species of butterfly. In the film, this CID also helped authorities eliminate individuals who came forward falsely claiming to be "Buffalo Bill," the serial killer’s nickname, in an attempt to gain fame. Since these individuals were unaware of the concealed detail, it allowed investigators to quickly rule them out, saving valuable time.

In almost every investigation case, there are unique characteristics — clear and distinct markers that differentiate the case under investigation from other cases. A clear and distinct unique detail, known to both the investigator and the suspect and linking the suspect to the case, will be used for the purpose of verifying and substantiating the suspicion.

For illustration purposes, let us consider a hypothetical case in which the security manager receives a report of a theft, allegedly committed by one of the organization's employees. During the initial inquiry, it is discovered that one of the management offices was broken into, and several items were stolen from a blue electronic safe that had been hidden behind a picture on the wall. The stolen items included: a Canadian passport, a diamond ring, and approximately $1,000 in cash. It is crucial to ensure that these unique details are not disclosed to the suspect or to any other individuals during their interrogation regarding the incident, nor to anyone outside of the investigative team.
If it is later decided to conduct polygraph examinations for the suspects, the security manager must provide these details to the examiner, who will incorporate them into the polygraph tests conducted using the Concealed Information Test (CIT) method.
As a rule, the concealed detail (CID) should not be placed as the first option in any question, but rather in the second, third, fourth, or subsequent alternatives. See the positioning of the CIDemphasized):

1. Did you take from the safe located in the office that was broken into:
a. A gold watch, a silver ring, and approximately $50,000 in cash?
b. An American passport, a gold ring, and a bag of diamonds?
c. A Canadian passport, a diamond ring, and approximately $1,000?
d. 3 kilograms of gold and approximately $100,000 in cash?
e. 2 kilograms of gold and a German passport?

2. Do you know for certain that the color of the safe from which the items were stolen during the incident is:
a. Gray
b. Yellow
c. Black
d. Blue
e. White

3. Do you know for certain that the safe from which the items were stolen during the incident is located:
a. Fixed to the floor in the corner of the office
b. Under the desk in the office
c. Inside the office cabinet
d. In the office restroom
e. Behind a picture on the office wall

A subject who is uninvolved in the incident and has no connection to it is expected to answer all the questions in the negative and should not exhibit any different physiological response during the examination to the CIDs (marked here in red for the purpose of the article), as these details are neither known nor familiar to them and therefore should not be recognized.

In conclusion,
Concealed Investigation Details (CIDs) are a critical tool, both for substantiating a suspect's confession to committing an offense and for conducting polygraph examinations of suspects who claim to have no connection to the incident or any related information. It is of utmost importance to safeguard the CIDs and to use them properly — whether when obtaining a confession from a suspect or during a polygraph examination. Every effort must be made, to the fullest extent possible, to prevent the public disclosure of CIDs and to avoid revealing them to the suspect during interrogation or questioning.