Why perfectly normal people confess to crimes they never committed.

Just before 9am on July 30, 2002, Karen Boes walked out of her Michigan home, jumped in her car and went to visit her then-husband’s work.

After popping by, she headed down to a local Burger King, picked up an iced tea and met a friend for a spot of shopping.

As she ran her errands, drunk her tea and socialised, her 14-year-old daughter Robin perished in the family home, engulfed by flames that spread with ferocious intensity. The fire – one that quickly made its way to Robin’s bedroom from the hallway outside her door – was spotted just five minutes after Karen left the house.

Karen was the immediate, and only, suspect.

After sitting through 16 hours of videotaped interrogation, she incriminated herself, police said. Small hints placed her at the scene of the crime, before the fire took hold.

Or so they say.

Karen Boes, the centre of a new Netflix documentary The Confession Tapes, believes the reason she has served 15 years for her daughter’s death centres on a confession she never meant to give.

“I was falsely accused and convicted of the murder of my precious 14-year-old daughter, Robin Lynn Boes,” the 61-year-old said in a letter sent from prison, according to Michigan local news.

“The state had absolutely NO evidence against me and we were able to solidly establish that I was with a friend shopping in a city 30 miles away at the onset of the fire that took my daughter’s life,” she wrote.

In statements made while testifying, Boes said after hours and hours and hours of interrogations, she began to question if she was going slightly “insane”.

“I was starting to believe, yes, it was a possibility. How do you know if you went insane? The truth is that I had absolutely nothing to do with the fire.”

It’s a strange premise, the idea that a sane person would falsely confess to the murder of their own child. But according to criminal psychologist Tim Watson-Munro, not an altogether unlikely one.

According to Watson-Munro, the idea that someone would accidentally, and falsely, confess to a crime they didn’t commit happens “far more often” than anyone perhaps realises. It’s just hard to get statistics on, he says, because there are varying reasons and circumstances why someone may wrongly confess.

Watson-Munro tells Mamamia those who falsely confess can “roughly” be separated into three distinct categories.

"The first kind are people who knowingly and willfully make a false confession, because they want a sense of notoriety and so on, particularly when it comes to the big, high-profile cases," he says.

Cases where murder is involved, or where a child is abducted, attracts a certain type of person. A person who "reads a bit of information in the press" and decides to confess to police about something they had no involvement in.

"They are just attention-seeking. Those people can be mentally disturbed or of course experiencing psychotic delusion - delusion of references it's called. They convince themselves they committed the crime."

Others that fall into this category - a category characterised by the fact the suspect is generally aware they aren't guilty, but confesses anyway - are those who may have committed a separate crime in the past, and have "pervasive guilt about it".

Their thought process goes something like this: I didn't get punished for the other crime, so perhaps I will confess to this one. 

Unsurprisingly, Watson-Munro says, "they don't aren't think[ing] straight".

"There are others who might confess to something to protect others. Maybe they are connected to the underworld or maybe they are doing it in order to protect their families."

Then, there's a second type of person.

The second group of people who falsely confess to crimes are those who, like Karen Boes, find themselves overwhelmed by police pressure and give in to intrusive and accusatory lines of questioning.

"There are others who can't stand the pressures over them - they may be psychologically vulnerable or people with intellectual disabilities. I have seen a lot of cases where the police have stitched them up beautifully. They can't withstand those types of pressures.

"I don't think you can overestimate [the pressure of] being in a room with a bunch of cops, if you're psychologically vulnerable."

Watson-Munro says this kind of accidental confession is the "most common", though there are more safeguards in place to protect the psychologically vulnerable now.

How police forced a confession from Daniel Morcombe's killer. Post continues.

For example, in October 2010, Victoria Police released a revised version of its police manual, following a major revision of the rules for questioning those with mental health issues, cognitive impairment and disability. Those that may fall within their guidelines of what it means to be a "vulnerable person" must be joined by an independent third party when questioned by police.

So, can anyone of any level of intelligence fall victim to intense lines of questioning and interrogations?

"It's not just about IQ, there are people with an average IQ or even higher who may not be street smart or might be not be used to the dynamic of being in the police station. It can be quite a jolt to be arrested, and can be quite traumatising ending up in a police cell where you may be left alone for a long period before you're spoken to.

"You become extremely vulnerable to those kind of pressures."

Finally, there's a third category. A person who comes to believe they are guilty, even though they aren't, far away from the coercion of police. Watson-Munro says these people may be victim from external pressures from family and social circles.

Most often, he says, this happens in intense communities where there is a risk you may get shunned. So, some may confess to a crime they never committed with "catastrophic consequences".

Back in the US, the propensity for false confessions to incriminate the wrong suspect is just as pervasive.

According to The Innocence Project, 26 per cent of its 351 clients who were convicted of crimes, only to be exonerated by DNA, involved false confessions.

Of course, these confessions have monumental impacts on the lives of those who confess, and the family and friends in their orbit.

But, according to Tim Watson-Munro, "the bottom line is, it wastes time, ties up community resources and is a huge expense to the public".

And for someone like Karen Boes - who argues she has been falsely imprisoned for 15 years - the cost is one that can't be refunded.

For more Mamamia true crime:

• TRUE CRIME: Robert Coombes murdered his mother at 13. Then, he went to the cricket.
• Why the case of Monica Schofield will haunt Peter Cox for the rest of his life.
• Womb raiders: A history of a horrific crime committed overwhelmingly by women.