> it instructed the interrogator to attempt to obtain knowledge through the torture that only the guilty could have
This (AIUI) is currently used in Japan (without the torture). It's not a cast-iron guarantee against false confessions:
> Article 38 of Japan's Constitution categorically requires that "no person shall be convicted or punished in cases where the only proof against suspect is his/her own confession," In practice, this constitutional requirement take a form of safeguard known as "revelation of secret" (Himitsu no Bakuro, lit "outing of secret"). Because suspects are put through continuous interrogation which could last up to 23 days as well as isolation from the outside world, including access to lawyers, both the Japanese judiciary and the public are well aware that confession of guilt can easily be forced. Consequently, the court (and the public) take the view that mere confession of guilt alone is never any sufficient ground for conviction.
> However, most miscarriage of justice cases in Japan are, indeed, the results of conviction solely based on the confession of the accused. In these case, (1) the record of sequence and timing of the police discoveries of evidence and the timing of confession is unclear (or even faked by the police) (2) the contents of the revelation of secret has only weak relevance to the crime itself or that (3) the revelation of secret to be actually vague enough that it is apply only loosely to the elements of crime (Prosecutor's fallacy). Serious miscarriage of justice cases in Japan involve police deliberately faking the police evidence (and insufficient supervision by the prosecutor to spot such rogue behaviour) such as where the police already knew (or suspected) the location of the body or the murder weapon but they fake the police record to make it appear that it is the suspect who revealed the location. During the 1970s, a series of reversals of death penalty cases brought attention to the fact that some accused, after intensive interrogation signed as-yet unwritten confessions, which were later filled in by investigating police officers. Moreover, in some cases, the police falsified the record so that it appear that the accused confessed to the location where the body was buried, yet the truth was that the police had written in the location in the confession after the body was discovered by other means. These coerced confessions, together with other circumstantial evidence, often convinced judges to (falsely) convict.
> Serious miscarriage of justice cases in Japan involve police deliberately faking the police evidence (and insufficient supervision by the prosecutor to spot such rogue behaviour) such as where the police already knew (or suspected) the location of the body or the murder weapon but they fake the police record to make it appear that it is the suspect who revealed the location.
It's also not difficult for police to do this purposely or even by accident when they don't know the information yet, but there are only a small number of plausible answers to the question. So they ask you two dozen questions that each have five plausible answers, investigate the answers you give and five of them turn out to be correct by random chance. Then the wrong answers are forgotten or written off as a guilty person casting misdirection while the probability of each correct answer is incorrectly multiplied by the others to produce a strikingly inaccurate probability result.
This (AIUI) is currently used in Japan (without the torture). It's not a cast-iron guarantee against false confessions:
> Article 38 of Japan's Constitution categorically requires that "no person shall be convicted or punished in cases where the only proof against suspect is his/her own confession," In practice, this constitutional requirement take a form of safeguard known as "revelation of secret" (Himitsu no Bakuro, lit "outing of secret"). Because suspects are put through continuous interrogation which could last up to 23 days as well as isolation from the outside world, including access to lawyers, both the Japanese judiciary and the public are well aware that confession of guilt can easily be forced. Consequently, the court (and the public) take the view that mere confession of guilt alone is never any sufficient ground for conviction.
> However, most miscarriage of justice cases in Japan are, indeed, the results of conviction solely based on the confession of the accused. In these case, (1) the record of sequence and timing of the police discoveries of evidence and the timing of confession is unclear (or even faked by the police) (2) the contents of the revelation of secret has only weak relevance to the crime itself or that (3) the revelation of secret to be actually vague enough that it is apply only loosely to the elements of crime (Prosecutor's fallacy). Serious miscarriage of justice cases in Japan involve police deliberately faking the police evidence (and insufficient supervision by the prosecutor to spot such rogue behaviour) such as where the police already knew (or suspected) the location of the body or the murder weapon but they fake the police record to make it appear that it is the suspect who revealed the location. During the 1970s, a series of reversals of death penalty cases brought attention to the fact that some accused, after intensive interrogation signed as-yet unwritten confessions, which were later filled in by investigating police officers. Moreover, in some cases, the police falsified the record so that it appear that the accused confessed to the location where the body was buried, yet the truth was that the police had written in the location in the confession after the body was discovered by other means. These coerced confessions, together with other circumstantial evidence, often convinced judges to (falsely) convict.
https://en.wikipedia.org/wiki/Criminal_justice_system_of_Jap...