Even the most horrible criminals feel guilt, and according to new research from the University of Montreal, playing on that sentiment might be a good way to extract a confession. In order to gain a better understanding of why and how criminals admit to their crimes, Michel St-Yves, a forensic psychologist and lecturer, and lead author Nadine Deslauriers-Varin, both of the university's School of Criminology, worked with 221 prisoners from a federal penitentiary, analyzing the conditions under which they did or didn't confess.

The study findings highlighted the predominant role of police evidence over and above other factors the researchers considered. When evidence is strong, the confession rate increases independently of sociodemographic or criminological factors. However, when the police evidence is weak, the researchers found that a confession is more likely if there are feelings of guilt about the crime, if the suspect is single at the time of the interrogation, has prior convictions and was convicted for a more serious crime.

Other recent studies also show the "relationship" is an important factor during the interrogation, and that the police interrogator's attitude plays a significant role. "Confessions mostly rely on how the interrogation is conducted and it's nothing short of an art form," St-Yves said. "It's an art that must be practiced with finesse seeing as the accused is never obliged to answer questions and that all coercive methods or promises used by police will eventually be rejected by the courts." St-Yves believes criminals feel the urge to confess for various reasons: to unburden themselves, to blame a third party, to make their crime more acceptable in the eyes of others or their own eyes, or in the hope of obtaining a lighter sentence.

Among the prisoners who volunteered for the study, 45 percent had confessed to their crime, which is slightly lower than the 50 percent confession rate concluded by other studies. This slightly weaker percentage could be due to the fact that the study was undertaken in a penitentiary environment, and by the fact that in addition to their prior criminal record, the subjects of the research had received federal sentences for very serious crime. The confession rate of first-time offenders was 80 percent and 51 percent for repeat offenders.

St-Yves will continue his research in the hope that more scientific interrogation methods will result in a more effective and efficient justice system. The researcher also noted that the use of cameras in interrogation rooms is a good thing as it limits coercion, and in terms of transparency for the courts, it's the best possible way to witness just how the interrogation was undertaken. The team's findings were published in Justice Quarterly, a peer-reviewed journal.

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