Over the next several months, defense lawyers for Pedro Hernandez will seek to undercut the central evidence against him: his videotaped confession to having killed 6-year-old Etan Patz.

They will depict the confession as inaccurate when set against the known facts of the infamous 1979 missing child case. They will portray Hernandez, a onetime bodega clerk in the Manhattan neighborhood where Patz lived, as mentally ill. They will paint the detectives who gained the confession as manipulative and coercive.

It's a daunting assignment, but here's what may well be scaring the lawyers the most: They could succeed in every aspect of their attack on the reliability of the confession and still not win an acquittal.

Such is the power of confessions, true or false, for American juries. A nascent body of scholarship, driven in part by an escalating number of wrongful convictions in cases with false confessions, has begun to document just how persuasive confessions can be.

Of course, the power of confessions owes in part to the fact that they very often are true. Certainly, that is the argument Manhattan prosecutors will make as they seek to hold Hernandez responsible for a case that has haunted the city, and parents nationwide, for decades. Prosecutors say Hernandez's claims that he strangled the young boy after luring him from his school bus stop are credible, and that any mental health issues he suffers from are not serious. They also argue that the confession is supported by the accounts of others who maintain Hernandez told similar stories of killing a child over the years.

But false confessions – including those questioned at trial by effective defense lawyers – also have proven to carry extraordinary weight with juries. Several studies, using mock jurors and sophisticated analysis, have demonstrated that confessions outweigh the value of eyewitness and character testimony. And in at least one case, according to a 2010 study, prosecutors chose to believe a confession even when the accused seemed categorically cleared by DNA evidence.

That 2010 study, which appeared in Cornell Law School's Journal of Empirical Legal Studies, produced and reflected on some fascinating insights into the otherwise under-examined universe of juror belief and behavior.

• Jurors believe they can better judge a confession's truthfulness if it has been videotaped, as opposed to audiotaped or written out (Hernandez's confession was videotaped.)  Still, barely 40 percent of jurors interviewed were confident they could determine whether a videotaped confession was truthful. The study also remarked that jurors were more likely to regard a videotaped confession as truthful if the tape involved only the accused. They were less inclined to accept the confession when the tapes included the accused's interrogators.
• Jurors tended to believe that police officials were better equipped to evaluate confessions than ordinary citizens, even though a 2005 study showed police actually performed less well than college students in a lie detection experiment. In the 2010 study, non-white jurors were less inclined to regard police as better suited to assessing the truthfulness of confessions.
• The 461 mock jurors used in the study said there was a better than 50-50 chance that a jury "would convict a suspect who falsely confessed to a murder, even when there was no other evidence that he or she was guilty."

On Thursday, the judge in the Patz case was still working to seat a jury. To date, Judge Maxwell Wiley has kept aspects of the case out of public view. The questioning of some jurors has taken place in secret, and the content of those interrogations kept under seal. The actual videotaped confession, while having been played in open court, has also been kept from the public and news organizations. And at least two hearings on what evidence will be admitted during trial have also been kept under seal, including one on Thursday.

Not surprisingly, then, the lists of witnesses to be called by both sides have not been made available. And thus whether Hernandez's defense team plans to call expert witnesses to testify on the phenomenon of false confessions is unclear. The value of such testimony, however, was endorsed by the state's highest court in 2012.

"That the phenomenon of false confessions is genuine has moved from the realm of startling hypothesis into that of common knowledge, if not conventional wisdom," ruled Judge Susan P. Read of the New York State Court of Appeals.

Hernandez's confession, again, might well be accurate. If so, and he is convicted, it will be a significant accomplishment for prosecutors who have kept an open file on the case since Patz went missing on his first day of going to school alone.

But in the nearly three years since Hernandez's highly publicized arrest, some experts and law enforcement officials have expressed doubts about the confession's reliability. Hernandez, as well as the circumstances of his confession, raise the array of red flags looked for when assessing potentially false confessions: a history of mental illness; a long interrogation (it lasted over the course of 36 hours, much of it not recorded); the crime having been recently the subject of widespread media attention (weeks before Hernandez confessed, a development in the Patz case had been front page news in New York).

Hernandez's trial is expected to last two to three months. The confession will be played, maybe played repeatedly. And the jury will have to decide what to make of it. And when they do, there will be more material for experts on confessions to study. On how juries regard them, on how judge's handle them, on how expert testimony can help the process or not.

 "In the area of interrogations and false confessions" the 2010 study said, "there has been relatively little research exploring the beliefs and abilities of key actors in the legal system such as judges, police and jurors."

Related coverage: For more about the disappearance of 6-year-old Etan Patz, read the story ProPublica produced with WNYC in 2013 and our story about Hernandez's confession. And learn more about the questionnaire potential jurors were asked to fill out.