Martin Bryant's chilling police interview after he was arrested for the Port Arthur massacre

Martin Bryant's chilling police interview after he was arrested for the Port Arthur massacre

Warning: Graphic content.

AS an angelic-looking child, Martin Bryant was already displaying the telltale behavioural signs of a future killer.

For one, he had an obsession with fire.

When he ended up in hospital after setting himself alight with fireworks the 12-year-old calmly told a news reporter he would still play with them. Neighbours also claimed he had set fire to a hospital as a boy.

Another problematic behaviour Bryant displayed was cruelty to animals.

With his air rifle, Bryant loved to shoot birds and other fauna near his Tasmanian home and then delight in watching them die and pumping extra slugs into their bodies.

Sure enough, the blue-eyed blond-haired boy grew up to become a lonely young man obsessed with weapons.

Late on a Sunday morning in April 1996, the 28-year-old Bryant took his guns and killed 35 people. At the time he was the world’s most deadly lone gunman.

Bryant clearly had two key behavioural traits of what is known as the Macdonald Triad, a combination of three factors which claim to predict the early behaviour of future mass or serial killers.

The third factor in the Macdonald Triad is bed-wetting past the age of five - although it’s not known whether Bryant displayed this trait.

US psychiatrist John Macdonald, who first described the homicidal triad, argued that a prospective killer required a combination of two or all three factors.

Bed wetting was the most controversial of McDonald’s proposed traits, with psychologists and criminologists now discounting this, saying it is cruel to tarnish children who suffer from this condition with the suggested blight of future violence.

It is certainly clear that many children who bed wet are not destined for a life in any way associated with violent crime.

In the years since McDonald put forward his theory, researchers have agreed that many violent offenders do indeed show these traits in childhood - although it is rare for an offender to show all three.

But Macdonald found that more aggressive and psychotic people were more likely to have a history of fire-setting, cruelty to animals and persistent bed-wetting past a certain age than subjects who were not aggressive or psychotic.

Later reserach found that all of these traits were also linked to childhood abuse and neglect and that this in turn made children prone to homicidal tendencies.

The Macdonald Triad also gave rise to other homicidal triads theories.

The Federal Bureau of Investigation (FBI) developed its own triad, which paired being abused as a child and reacting by torturing animals, as giving rise to becoming violent to humans.

Some of the world’s worst killers are known to have displayed these traits.

Cannibal killer, Katherine Knight

As an indication of what she would later do to her partner John Price, cannibal killer Katherine Knight once cut the throat of her boyfriend’s two month old puppy in front of him.

Knight had a violent childhood and became known for “uncontrollable rages” at school which she left early for her “dream” job cutting meat in an abattoir in the NSW Hunter Valley.

Knight was so skilled with knives she was promoted to the abattoir’s boning room.

On her wedding night, she tried to strangle her first husband.

When her first child was a baby, Knight placed her daughter on a railway track, then stole an axe and threatened people in town.

She slashed the face of a woman with her boning knife.

In a later relationship, with miner David Saunders, she stabbed him in the stomach with a pair of scissors.

But it was in her relationship with John Price that Knight’s violent fantasies would reach their peak.

Their “romance” was volatile, with Knight often threatening to kill Price.

On February 29, 2000, following a series of assaults by Knight, Price threw her out of his house and took out an Apprehended Violence Order against her.

That evening, while he was sleeping in his house, she stabbed him 37 times.

Using her prized boning knives, she decapitated his body and flayed him, hanging a skin “suit” from a meat hook on the living room door.

Then she boiled up his head on his kitchen stove with vegetables and made gravy and set the table with place names for his children.

In a further act of defilement, she arranged his body with one arm draped over a beer bottle.

In prison, where she is serving a life sentence, she has turned to Christianity and choral singing.

The Co-ed butcher, Edmund Kemper

American serial killer, necrophile and suspected cannibal who abducted and murdered seven college girls began torturing cats around the beginning of his adolescence.

Kemper also killed his mother and his grandparents to “see what it felt like”.

During his childhood, Kemper began by cutting off the heads of his sisters’ dolls and played a game in which he had them blindfold him and he would pretend to die in a gas chamber.

When he went to live on his grandparents’ farm, he began shooting birds and other animals with his rifle.

When his grandparents took away the rifle, he killed them, aged 15.

Kemper was released at the age of 21, and within a few years began picking up female hitchhikers and killing them.

He would shoot, stab, smother or strangle them, then bring the bodies back to his apartment to defile them further.

At the age of 24, in 1973 Kemper murdered his mother and then his mother’s friend and then called police to confess his crimes.

BTK killer, Dennis Rader

Dennis Rader became known as the BTK killer, for what he did to his victims — bind, torture and kill.

But first he discovered as a child that he enjoyed binding, torturing, and killing by experimenting on animals.

He also had a sexual fetish for women’s underwear and later stole underpants from his victims and wore them himself.

Rader would go on to murder at least ten people in the US state of Kansas between 1974 and 1991, but police believe there were many more victims he lured and killed.

After some of the murders, Rader would send letters describing the details with his infamous “BTK” signature.

Milwaukee cannibal, Jeffrey Dahmer

Jeffrey Dahmer killed 17 young men and boys, beginning at the age of 18.

But he had started abusing animals aged ten, and his fascination with mounting and keeping body parts began with animals.

His later murders involved necrophilia, cannibalism, and the preservation of body parts, including heads and skeletons.

The elder child of a tense marital relationship and an anxious mother, he was a quiet child.

Early on, he had a fascination with animals, collecting dragonflies and butterflies and storing them in jars.

He progressed to collecting animal carcasses from the roadside, which he would dismember, and place the parts in jars which he kept in a garden shed.

Young Jeffrey was fascinated with the way animals “fitted together”, and played with and collected animal bones.

By the age of eight, he became reclusive and started cleansing bones in bleach.

In high school, he was a social outcast and began abusing alcohol and discovered he was homosexual.

By the time he was 18, Dahmer’s parents had divorced and just three weeks after graduating from high school, in 1978, he committed his first murder.

The victim was an 18-year-old male hitchhiker who Dahmer spent several hours with drinking and listening to music and then hit with a dumbbell and then strangled to death.

Dahmer dissected the boy’s body and dissolved some of he flesh with acid and crushed the bones.

Over the next nine years, Dahmer would enter Milwaukee’s gay scene, and pick up some of his victims in gay bars.

In 1987, he picked up a man in a bar, killed him and then transported the body in a suitcase to his grandmother’s house.

He then dismembered the body, but kept the head.

Following this, Dahmer actively sought victims and murdered 15 more men and boys.

He was arrested in 1991 when one intended victim escaped and flagged down the police, Dahmer’s handcuffs still attached to his wrist.

Jeffrey Dahmer was sentenced to life in prison, but in 1994 was bludgeoned by two fellow inmates and died two days later.

Son of Sam, David Berkowitz

Serial killer David Berkowitz was convicted of six shooting murders and two further attacks in New York in 1976 and 1977.

The attacks terrorised the city as bodies piled up and Berkowitz eluded a massive police manhunt.

His nickname Son of Sam came from the fact that he believed he was obeying the orders of a demon who told him to kill.

The demon manifested in the form of a dog “Harvey” who belonged to his neighbour “Sam”.

As a child, Berkowitz had been a deeply disturbed firesetter and animal torturer.

Adopted out by his birth mother, he began stealing and lighting fires at a young age.

He is believed to have set around 1400 fires.

He began to torture animals at the age of ten.

By 17 he had started to commit violent crimes, attacking young female victims with a hunting knife.

His shooting spree began in July 1976 when he crouched beside a car parked with two young women, raised a .44 Bulldog revolver and killed one, and wounded the other.

Berkowitz then turned and walked away quickly, without saying a word

It was to be the signature of all his crimes.

Berkowitz started leaving notes with his victims’ bodies calling himself “Son of Sam”.

At one point during his crimes, he shot his neighbour’s dog

After he was finally arrested and pleaded guilty to all the shootings, Berkowitz said “In all honesty, I believe that I deserve to be in prison for the rest of my life”.

The Boston Strangler, Albert DeSalvo

As a child, Albert DeSalvo trapped dogs and cats and shot arrows at them through boxes.

Born in Massachusetts he was the son of a violent alcoholic father who tortured and abused DeSalvo’s mother.

In his teenage years, DeSalvo began stealing and using the animals he trapped in boxes for archery practice.

As a 12-year-old, he was arrested for theft and battery and sent to a boys’ reform school.

He briefly joined the US Army and by mid-1962 began strangling women in the city of Boston.

The victims were women of all ages living alone.

Mostly they were strangled in their homes with articles of their clothing, although two were stabbed to death.

The unidentified killer became known in the media as the “Boston Strangler”.

Around the same time, a series of rapes was committed in the Boston area.

After one rape in October 1964, the victim was able to identify DeSalvo and when his photograph was published, other rape victims came forward.

Arrested for the rapes, DeSalvo gave a detailed account of his killing spree as the Boston Strangler.

Imprisoned for life, he later withdrew his Boston Strangler confessions.

DeSalvo was stabbed to death in prison in 1973.