After honor student Stephanie Crowe was stabbed to death in her bedroom in Escondido, California in January 1998, police briefly questioned (and collected clothes from) Richard Tuite, a drug-addicted, mentally ill transient who had been spotted prowling nearby the previous evening and scaring the Crowes’ neighbors. But the first person to get the third degree by detectives was Stephanie’s 14-year-old brother Michael, who weathered 10 hours of grueling interrogation without his parents or attorney present.

Michael was told – falsely – that his 12-year-old sister’s blood was found in his room, that his hair was discovered between her fingers and that his voice stress analyzer test showed deception. Eventually, Michael cracked. He told detectives he had no memory of the crime, but he would be willing to make something up for them.

The desperate teenager’s taped confession is now infamous, heavily interspersed with red flags like: “OK, here is the part where I’ll stop lying.” At one point, veteran detective Ralph Claytor asked him, “How many times did you stab her?” “It’s going to be a lie,” Michael responded. “Three times.” “How many?” Claytor repeated. “Three,” said Michael. “It’s a lie.”

The teen quickly recanted and wouldn’t sign a written “recap” statement. But now-retired Detective Claytor had no doubt that he had his killer. After all, the investigator observed, Michael seemed less grief-stricken than his family and while at the police department, during lunch the boy watched cartoons and played a video game.

Michael was arrested along with friends Joshua Treadway and Aaron Houser. After 13 and a half hours of videotaped interrogation, Treadway confessed that the trio plotted to kill Stephanie. The three boys were charged with murder and spent almost six months in juvenile hall.

But after a judge reviewed those videotapes and questioned the interrogations’ legality, the boys were released. Michael’s and Treadway’s confessions were judged to have been coerced and the judge threw them out. Still, San Diego County prosecutors wanted to try the boys for Stephanie’s murder.

A year after Stephanie’s death, DNA testing identified three blood drops on transient Richard Tuite’s stained red sweatshirt as belonging to Stephanie Crowe. Later, blood drops were also found on Tuite’s undershirt. In 2004, Tuite was convicted of killing Stephanie and sentenced to 13 years for voluntary manslaughter. In 2011, Tuite was awarded a new trial over a prosecution witness whose credibility the defense was not allowed to question.

Blood or no blood, Claytor remained steadfast that the boys were responsible. In a deposition he gave five years after the murder as the Crowe family sued the city of Escondido over Michael’s ordeal, he said “Joshua Treadway and Michael Crowe said they did it,” said Claytor. “So I’d have to say that, since they’re the ones who told me they did it, they’re the ones who did it.” The Crowes eventually settled for $7.25 million, and in May, Michael Crowe – now married and a first-time father – got his wish to be declared “factually innocent.” While all three boys were exonerated in 2002, Crowe pushed for this unusual declaration to remove any lingering doubts about their innocence.

According to psychologists, the intransigence on the part of the lead detective and others in the Crowe case was, as it was in the Marty Tankleff case both predictable and understandable. No matter if science can debunk old “evidence” used to win a conviction, no matter if overwhelming information is uncovered to prove an innocent was wrongfully imprisoned, some key players – detectives, prosecutors, fire marshals, et al – will cling to their long-held certainty about a suspect’s guilt.

“It’s always easier to recognize the mistakes of others,” cognitive neuroscientist Itiel Dror says of these often mystifying denials. “The problem we face,” says social psychologist Carol Tavris, “is not from bad people covering up their mistakes and not wanting to face the truth. It’s from good people who deny the evidence in order to preserve their belief that they’re good people.”

Anthony Greenwald, a psychology professor at the University of Washington, says it’s natural for most of us to see ourselves in the most favorable light possible; to picture ourselves as more heroic or good or honorable than we are. For some, accepting that they may have contributed to an injustice would be such a massive blow to their perception of themselves that it is simply intolerable to countenance. So they don’t.

“People perceive themselves readily as the origin of good effects and reluctantly as the origin of ill effects,” says Greenwald. “I don’t think there’s anything special in thinking that this applies to people who work in law enforcement. The only thing one needs to assume is that they, too, are human – like the subjects in all the research that demonstrates the phenomena.”

Self-justification is the powerful mechanism that blinds us to the awareness that we were wrong says Tavris who wrote Mistakes Were Made, But Not By Me: How We Justify Foolish Beliefs, Bad Decisions and Hurtful Acts with social psychologist Eliot Aronson.

“It’s a mechanism that allows us to maintain a consistency between our beliefs about ourselves, which are usually positive – ‘I’m a good, kind, competent, ethical person’ – and the cognitive dissonance that is aroused when I, a good, kind, ethical person, am confronted with evidence that I did something incompetent, unethical, immoral, hurtful, or cruel.”

Cognitive dissonance, says Tavris, is unconscious mental conflict that arises when two attitudes, or an attitude and a behavior, or an attitude and new information, are incongruous with one another. We quash any contradictory or conflicting thoughts that pop up, she explains, because accepting them would mean accepting that the initial decision was wrong – something which makes humans, from detectives to doctors, uncomfortable.

Dror believes there are also reasons why criminal justice professionals’ intractability may be heightened. One factor: the more time, effort and money invested in an investigation, the more crucial it becomes to justify past choices. While that might seem equally applicable to those in business or public office, criminal justice professionals get a different kind of feedback.

“When they make errors it is not clear that they do because the actual truth is not known,” says Dror, “When a doctor amputates the wrong leg, then it is clear a mistake has happened. No way out! However, in the criminal justice system, the court gives a verdict but we never do know if it is correct or not.” Working in our adversarial justice system also plays a part, says Dror. “It makes admitting to error very hard – not only in the specific case, but the implication for future cases.”

To Dror, all the work we put into “not admitting mistakes, not seeing mistakes, and building all this very elaborate dynamic rationalization to things you do” is an example of just how flexible and dynamic the human brain is.

“It’s because your brain all the time is building constructs that make sense of your behavior,” he says. “And people want to have a good self-image. The forensic examiners think they’re scientists, that they help the criminal justice system. And the last thing their brain wants to entertain is that they’re sending innocent people to jail.”

He notes that when people are asked to rank their driving skills, most will say “above average,” and that dynamic is widespread.

“Even when they have the data and they know what happened,” says Dror, “they always overestimate their success. We have to feel good about ourselves. People who suffer from depression have better memory than people who don’t, because part of our ability to survive and not to be depressed is to forget a lot of stuff.”

When detectives are certain they have the guilty party, says Tavris, whatever the suspect does further confirms their guilt. Law enforcement is generally taught, Tavris adds, techniques that confirm evidence rather than encourage re-examining it.

Why some see their errors while others doggedly do not is still something of a mystery. Although, says Tavris, psychopaths aside, people behave cruelly or just plain appallingly based on specific situations – just as they do with goodness.

Often, it’s those who come to a case later who end up working to correct conviction errors. With no time invested in or commitment to a particular outcome, it’s easier to be objective.

And the stakes are high. “The greater the harm, the greater the need to reduce the dissonance over having committed it,” says Tavris, “because that harm that you’ve done goes right straight to your gut and into your concept of yourself as a competent DA, or a competent cop, or a competent physician.”

Because human beings think in stories, says Tavris, the challenge is keeping an open mind and not locking into one belief or theory. Every step taken down a path makes it harder to step back. “It’s why people keep throwing good money after bad, or stay in an abusive or self-defeating relationship way longer than they should,” she says.

It’s critical to understanding the psychological stumbling blocks to admitting error.

Being unable to rely on those who make mistakes to correct them is reason enough, says Dror, to push to establish external review protocols and to inject impartial oversight into all levels of the system.

One improvement he’s seen: the FBI’s revised Standard Operating Procedures that help avoid bias in fingerprint examination. For example, examiners must now, they specify, “complete and document analysis of the latent fingerprint before looking at any known fingerprint.”

Dror says some crime labs are also adopting more procedures he’s advocated to counter cognitive and psychological contamination. And conviction integrity units and pre-trial reliability hearings also further these goals. The Conviction Integrity Program in the New York County’s district attorney’s office, for example, not only has a conviction integrity committee but also an outside Conviction Integrity Policy Advisory Panel. And in Texas, the non-profit Innocence Project of Texas is providing oversight for a review underway of that state’s arson convictions.

“You need to try to rectify whatever error you made,” says Santa Clara County, California, Special Assistant District Attorney David Angel. “But it needs to really shift from this kind of highly moralistic, punitive view. Maybe it’s a cause for embarrassment, but it’s not a cause for shame.”

He believes prosecutors have drawn the short straw in language, noting that defense attorneys who err are called “ineffective” and judges are “reversed” while prosecutorial error alone is labeled “misconduct,” with all the attendant negative connotations.

Angel believes that most prosecutors are willing to admit to mistakes but that “people are very hesitant to admit to something that’s called ‘misconduct,’ because it makes you feel like you did something morally wrong.”

We need to expect and accept and above all to learn from mistakes. Moving forward, Angel envisions using errors, harmless and otherwise, as study topics in in-house ethics training classes for prosecutors.