PSYCHIC UNDERSTANDING

The rape victims had told of an uncanny, almost psychic understanding between the two men who must have known each other for years.

One said: 'They didn't tell eachother anything. It was two bodies but one brain.'

Another added: 'The two men seemed to be able to communicate without words - by nodding their heads.'

The pair had been almost joined at the hip since they met at in their first days at Haverstock Hill secondary school in North London. Mulcahy would later tell police his friend became 'almost part of the family.'

As they grew up together Mulcahy began to tower over Duffy physically and mentally, who never exceeded his schoolboy height of 5ft 4 inches and was referred to by Mulcahy as 'the midget.'

Both youngsters lived near Hampstead Heath and enjoyed 'spooking' the courting couples and homosexuals who gathered there.

They developed a love of the martial arts, spurred by the Kung Fu craze of the early 70's. Together they would relentlessly practice the powerlocks and holds which would later be so effective in trapping their victims.

OBSESSION WITH CRUELTY

They also began to share an obsession with the excitement they found in cruelty and crime.

Duffy's wife Margaret Mustafa told the Old Bailey how he would rape her during bondage sex sessions and terrorise their German Shepherd dog Toby.

Mulcahy would cheerfully tell the jury how he had bound a 12-year-old cousin hand and foot and tossed him into a bathful of ice cubes because the lad had difficulty getting out of bed. Mulcahy bellowed with laughter as he snapped photographs of the boy floundering in the melting ice.

In 1976 the pair were convicted of causing actual bodily harm when they shot four victims with an air rifle for fun. Shortly afterwards Mulcahy suggested they should rape a woman together.
Their 'wicked bond' was cemented by deep feelings of sexual inadequacy - Duffy's irrational hatred of women sprang from a low sperm count which prevented him from fathering children. Throughout his life Mulcahy had been troubled by difficulties in maintaining an erection which would drive him to escalating sexual depravity and violence in an attempt to arouse himself.

POWER OVER LIFE AND DEATH

'Duffy was the serial rapist. It was his partner who had that aggressive streak and the one who had the desire to dominate and exercise power and control over life and death,' said prosecutor Mark Dennis.

'Mulcahy was getting more out of this. He wanted something more than just rape.  It was the taller man who enjoyed exercising power over their victims, tormenting them, humiliating them on occasions.

'Mulcahy was an arrogant and cruel character playing with his victims as if the whole thing was a game, getting satisfaction and enjoyment from bullying and picking on the vulnerable.'

According to Duffy, they plotted their first rape because Mulcahy hated the owner of a house in Hendon, north London, and wanted to sexually assault her to 'teach her a lesson.'

They broke in but the woman failed to come home. Another planned rape at a house in Notting Hill, west London failed when the woman returned home with a male friend.

In 1981 they escaped with suspended sentences at Alton Magistrates Court when they stole wines and spirits from a store room.  Just over a year later the pair would carry out their first rape attack in a series of crimes which horrified Britain.

THE RAPIST'S KIT

The pair armed themselves with a 'rapist's kit' of balaclavas, knives and tape to gag and blindfold their victims.

Soon the Michael Jackson tape 'Thriller' would become another essential part of the kit.

'It seemed to motivate them as they drove, singing along, looking for victims,' Mr Dennis said. 'A substantial part of the thrill came from the anticipation of the hunt.'

Several of the rape victims remembered Mulcahy blaming them when he could not maintain his erection in attacks of increasing sadism. He would stroke the women's hair tenderly, kiss their neck and ask: 'Are you a virgin?' as he removed her clothes.

Running his knife across his victim's lips he whispering threats to gouge their eyes out or slice off their nipples and revelled in their pure terror.

'He was no longer satisfied by the sexual aspect, but by power, control, violence and torment,' Mr Dennis said. It was the desire for the ultimate thrill, the power over life or death that would cost three women their lives.

RAPED CLUTCHING A TEDDY BEAR

A 21-year-old who was walking home from a party in Kilburn in north west London clutching a teddy bear, was to become their first rape victim in October 1982.

Using sticking plaster to stifle her screams, they dragged her into a garden where she was stripped, blindfolded and raped. The victim recalled: 'I put my hands up and the taller man said: 'Don't worry, it is a knife.'

In March of the following year they targeted a 29-year-old restaurant manager who was walking near Finchley Road railway station. But the woman bit Mulcahy's hand and despite being kicked and punched she put up such a struggle they let her go.

An American social worker aged 32 was attacked on Barnes Common almost a year later on January 20, 1984. Mulcahy and Duffy, who were in the area decorating Duffy's parent's home, stripped and raped her.

Their fourth victim was a 23-year-old grabbed at West Hampstead railway station and dragged across the tracks on June 3 of that year. She told the court: 'They had a knife and said they would cut me if I didn't do as I was told. All I could say was: ''Please don't hurt me.” They laughed as they passed the distraught woman afterwards in their getaway car, joking that they should offer her a lift.

GAGGED WITH TAPE

A girl of 22 was gagged with tape after she was seized on Highgate West Hill a month later on July 8. Fortunately the rapists fled when a neighbour called the police. When the girl was comforted she still had pieces of tape on her wrists, one of which would provide crucial evidence against Mulcahy.

A week later on July 15 two 18-year-old Danish au pairs were attacked on Hampstead Heath as they walked arm in arm laughing together. One said: 'He told me to take off all my clothes and lie down. Then he pulled his trousers down to his knees and lay on top of me.'

Three months later the pair were arrested when they were stopped in Mulcahy's Talbot Horizon with stolen building materials. A black balaclava was found in the car but the pair escaped with fines after Mulcahy told police he used the mask when he was working as a plasterer on dusty ceilings.

On January 26, 1985 they attacked a 20-year-old German au-pair under a canal bridge at Brent Cross. Her scarf was used as a gag and blindfold as she was bundled towards the nearby bridge.

STRIPPED NAKED

'The man without the knife sat down and undressed me. He was not rough but he stripped me naked,' she said. Once fluent in English, the woman has refused to ever speak or read the language again or tell her husband of the ordeal.

By January 30 the pair were back trawling Hampstead Heath where they selected a 16-year-old virgin. Duffy told the court Mulcahy was becoming so violent he broke off the attack fearing his friend would kill the girl.

On February 2 they tried again with a French au-pair who was also grabbed near the Heath but the attack was aborted when she screamed and struggled.

Duffy claimed he stopped another attack on a 23-year-old the following month because he was again worried about Mulcahy's behaviour when the victim was dragged to a flats near the Heath.

Desperate for another victim, the pair selected a 25-year-old solicitor's clerk on March 1 and raped her on a bench on the Heath. By now the sexual excitement on the hunt was not enough for Mulcahy, who was having more and more difficulty becoming aroused.

MEETING BY THE RIVER

Four days after Christmas 1985 they targeted Alison Day, who had been due to meet her fiance at his printing firm in Hackney Wick.
The 19-year-old near was snatched at Hackney Wick railway station and dragged to snow covered playing fields nearby.

After both men had raped Alison, she tried to escape and fell or was pushed by Mulcahy into the freezing water of a feeder canal. Duffy claimed he pulled her out, and Mulcahy was so excited by the incident he raped her again, then tore off a piece of her blouse to throttle her.

He recalled: 'She was saying things like ''It is only his moustache I have seen, I won't tell anyone, please don't hurt me.'' I was watching David and the girl. The next thing I noticed was he was putting some material round her neck and starting to twist it.'

Mulcahy later told his accomplice he had killed Alison because she might recognise them. But Duffy said: 'David actually enjoyed it, saying it gave him power - the decision over life and death. I remember him going on: ''It is God-like - having the decision over life and death.'''

COAT WEIGHED DOWN WITH STONES

Alison's sheepskin coat was weighed down with stones and she was hurled back into the water. She was found 17 days later, bound and gagged with her hands tied behind her back.

On April 17, 1986, 15-year-old Dutch schoolgirl Maartje Tamboezer was knocked off her bicycle with a length of fishing line stretched across the path - a technique Duffy had learnt from one of his favourite books, The Anarchist's Cookbook.

The teenager was marched across the fields between Effingham and East Horsley in Surrey and raped by Duffy, who claimed Mulcahy suddenly lost his temper.

'He was becoming very aggressive - hyper, shouting at the girl,' Duffy recalled. 'He then raised his fists and hit the girl. She crumpled to the floor. She was struck on the head, at the side. It was a swinging blow. I noticed he had a rock in his hand, or a stone. She just crumpled up and fell on the floor. I believe she was unconscious.'

GARROTTED WITH HER OWN BELT

Former altar boy Duffy said Mulcahy then ripped off Maartje's belt and looped it around her throat, telling him: 'I did the last one, you'll do this one. He passed me the belt. It had a piece of stick through it which was twisted and he gave it to me in my hand,' Duffy told the jury.

'I actually started twisting it while David turned away. I think I just got caught up in it. It is very difficult to explain. I just continued twisting until she was dead.'

Duffy said they both left the scene but Mulcahy returned and set Maartje's body alight, stuffing burning tissues into her vagina hoping to destroy forensic evidence.

Newly wed TV secretary Anne Lock, 29, still had the suntan from a dream honeymoon scuba diving off the Seychelles when she was ambushed getting off a train at Brookmans Park, Hertfordshire on May 18, 1986. When the pair spotted her bicycle in the station's shed they hid in the bushes and waited until she returned.

Duffy said he raped Anne, then Mulcahy threw him the a bunch a keys and he went to collect the car. He told the court: 'David said he had taken care of it. He was very evasive, like he was playing mind games. He was saying: ''She won't identify us now''. He was very excitable, buzzing. He was even saying: ''Keep your eyes open for another one.'''

MURDER BUZZ

Anne's decomposed body was found two months after she was murdered in undergrowth just a mile from her home. She had been suffocated with her own sock.

Ten years after the murder of Anne Lock, with Duffy safely behind bars Mulcahy must have believed he would never be caught. But on August 6 of 1996 another rapist sprang from the undergrowth in near Hampstead Heath, sparking a chain of events which would lead to Mulcahy joining his friend behind bars.

Ted Biggs, then 34, was a salesman at a bedding shop in Hitchin, Herts, leading the double life of a rapist by night.  He attacked 66-year-old woman on the Heath that summer's night and struck again in Hampstead in September 1998.

Police launched Operation Loudwater to track down Biggs, who would prey on six victims before he was jailed for life. By sheer chance one of the officers on Operation Loudwater, DC Caroline Murphy met DC John Haye in a pub. DC Haye had been the exhibits officer in the Duffy inquiry.

They quickly realised the two cases had striking similarities in location, and the knife and the balaclavas that were used.

THE NET CLOSES

DC Murphy called Whitehouse prison in Cambridge to make sure Duffy had not been let out on day release and could not be responsible for the offences. She learned Duffy was in fact being interviewed by psychologist Jenny Cutler, who told her Duffy had given the name of his accomplice as David Mulcahy.

All the surviving exhibits from the original case were re-examined and tested using DNA techniques which were not available in the 1980s.  Samples taken from the clothes of one of the au-pairs Mulcahy raped on Hampstead Heath showed there was only a one in a billion chance he was not the attacker.

Senior officers then found than in an astonishing blunder a piece of tape used to bind the woman attacked on Highgate Hill West had not been tested for fingerprints before it was consigned to the storeroom at Euston station. Their worst fears were realised when four experts confirmed the fingerprint they found on the tape belonged to David Mulcahy.

Tragically, Mulcahy and Duffy could have been stopped after just three rapes.

Mulcahy was convicted of three murders, seven rapes and five charges of conspiracy to rape after a trial lasting more than five months. The jury of six men and six women had deliberated for 19 hours and 42 minutes over four days.

DUFFY'S CONFESSION

Duffy was convicted of two murders, five rapes, and another sexual assault but cleared of Anne's murder at his trial. He later confessed to another nine rapes - including that of Anne Lock - six conspiracies to rape and two burglaries with intent to rape.

Described by the judge who sentenced him in 1988 as 'a predatory animal' Duffy is now thought to be one of Britain's most prolific rapists with up to 50 victims.

At the end of Mulcahy's trial in February 2001 The late Recorder of London Judge Michael Hyam told him: 'These were acts of desolating wickedness in which you descended to the depths of depravity in carrying the them out.' Duffy and Mulcahy will never be released.

"We would have balaclavas and knives. We used to call it hunting. We did it as a bit of a joke. A bit of a game."

by Paul Sutherland

The use of a profiler in modern police investigations is now quite a common practice, but for years the Police were fiercely opposed to what they considered to be “science fiction”. Television programmes such as “Cracker” and “Wire in the Blood” tend to glamorise and over exaggerate the use of Profilers, but it must be remembered that these are only television dramas. A psychological profile is only an investigative tool to be used, one must be careful that they do not focus solely on the profile and be influenced by this when they may have conclusive evidence to the contrary of the profile.

Famous British profilers include Professor David Canter, Dr Paul Brittain, Dr Julian Boon and Dr Richard Badcock. All have worked on high profile cases and have been responsible for bringing profiling out into the open for it to be understood and followed.

Britain’s first widely reported use of a profile was in the 1980’s case of the Railway murders. London, Surrey and the Home Counties police were alarmed by a series of rapes happening within their areas. Most of the attacks were carried out by two masked men, and police noticed that nearly all of the attacks happened near or leading directly from a Southern link Rail route, which showed that the offenders had a detailed knowledge of the Southern Railway network.

The attacks had started in 1982 and over the next 12 months the sinister duo raped another 18 women. In each case the attackers had taken the front door key from each victim as a ghastly “souvenir”. In several of the cases one of the attackers seemed almost ashamed of himself, several times apologising to the victims as the two men were fleeing the scene.

However, in 1983 the attacks mysteriously ceased, until 1984, when a solitary attacker began to attack women in West and North West London. The attacks carried on until July 1985, when the same man raped 3 women in one night. This outrageous crime led to the formation of Operation Hart, and detectives had managed to link 30 different attacks, all investigated under the above operation.

The only clue that officers had to go on was that the majority of the victims described the rapist’s eyes as being, "cold blue, staring, almost like lasers". The rapist was extremely violent and was a pervert. As if detectives did not have a serious enough investigation, the rapist was about to take a step further in his criminal career and kill for the first time.

19-year-old Alison Day left her home in Hornchurch, Essex, late in the afternoon of 29 December 1985 to meet her boyfriend, who worked at a local print works. She boarded a coach and made it to Hackney Wick railway station, where she planned to walk the short distance to the print works. The route she would have had to take led her down a darkened towpath alongside a canal, and it was whilst Alison was walking down this towpath that she met her killer.

Alison was forced at knifepoint to a block of rat-infested garages, and had her hands tied behind her with some coarse string in a "praying position". She was then savagely raped and strangled with a technique known as a “Spanish Windlass”. This involved a piece of the victims clothing being torn away and looped around her throat, then slowly tightened using a piece of wood to twist it.

Once she was dead, her killer weighted the body down using stones in her pockets, and threw the body into the nearby River Lea. It was not found until 15 January 1986, and, due to the amount of time the body had spent in the water, forensic evidence had all been washed away. However, fibres were found on the victims clothing, especially on a sheepskin jacket that could have come from the killer’s clothing.

Police shared their findings with the Operation Hart team, but apart from the obvious connection with the railways, there was nothing to connect the two cases. Police working on Operation Hart had already theorised that the rapist they hunted knew every alleyway, path and snicket around the London Rail network However, four months later, the killer struck again.

15 yr old Maartje Tamboezer was one of 3 sisters, the children of a Dutch businessman living in West Horsley, Surrey. On the afternoon of Thu 17 April 1986 Maartje was due to go on holiday the next day, and set off in the late afternoon to cycle to the nearby village of East Horsley, to buy sweets for the journey. When Maartje had not returned by early evening, her worried parents called Surrey Police.

Between Guildford and Leatherhead just adjacent to the A246 between the two, there is a dark spinney that runs alongside the railway line. Two men out ferreting here early on the morning of 18 April found Maartje’s body, which had been so vigorously mutilated that at first they did not recognise the remains as that of a human corpse. Maartje had been bound by the wrists with coarse string, savagely raped, and strangled with a tourniquet. There had also been an attempt by the killer to remove forensic evidence by setting fire to Maartje’s corpse. Her bicycle was found propped against a tree, and nearby, police made an unusual discovery.

There was a length of bright orange nylon wire stretched across the footpath at chest height. This obviously had been purposely set by the killer to force Maartje to dismount. Detectives surmised that she had been dragged into nearby woods at knifepoint, raped, beaten, and finally garrotted. As well as the nylon wire, the killer had also left an unusually small footprint. When the post-mortem report on Maartje came back, police noted with interest that one of her neck bones was broken, possibly caused from a karate blow in the opinion of the pathologist.

Surrey police launched their biggest ever manhunt, and their most promising lead came from the passengers on the 6:07 pm train from Horsley to London. The guard recalled a smallish man wearing a blue parka jacket rushing onto the platform as the train was departing, causing the guard to have to reopen the self-closing doors.

A young woman passenger recalled how the man had chilling, laser like staring eyes, and how he had gazed at her several times before she got off the train at Bookham. Police checked thousands of abandoned train tickets, in an attempt to recover the man’s fingerprints, but it was to no avail.

Police however, did have some good luck. They had managed to determine from semen left at the scene of the Tamboezer murder that the killer belonged to blood group A. They had also managed to nail the make of the string used to bind the victims. It was called Somyarn, and was not made of the usual cord or thread but was made of paper. It was traced to a batch made by a factory in 1982, but police could not trace it any further than this. They were still working on this lead a month after the murder of Maartje Tamboezer when news came in of another Railway attack.

29 yr old Anne Lock worked for London Weekend Television as a secretary, and worked late on the night of Sun 18 May 1986. Anne had only been married for a month, and had just returned from her honeymoon in the Seychelles. Anne usually took a train home from the South Bank studios where she worked, to Brookman’s Park near Potter’s Bar, Hertfordshire. It was dark when she arrived at Brookman’s Park at 10pm, and she quickly walked to the bicycle shed where she had left her cycle. When she got there, she found her way blocked with a bench dragged across the pathway. The trap was sprung.

The disappearance of Mrs Lock was massively publicised, and connecting her disappearance to the murders of Alison Day and Maartje Tamboezer, Surrey and Hertfordshire police set up a joint operation codenamed Trinity. This manhunt, which led on to Operation Hart, was to become the biggest undertaken in Britain since the Yorkshire Ripper inquiry of the 1970’s. Detectives had managed to narrow their initial list of 5000 suspects down to 1,999 men who fitted the description and other details of the Railway rapes and murders. Number 1,594 on the list was a slightly built Irishman, John Duffy, a British Rail carpenter.

Duffy had been placed on this list due to the fact that he had a history of violence and in August 1985 had been in trouble with police for raping his ex wife. Police took an extra interest in Duffy because on Saturday 17 May he had been arrested for loitering at North Weald Railway station. Detectives searching him found a sharp butterfly knife in his pocket, along with tissues and a box of matches. Duffy claimed he used the knife at his weekly martial arts class, near to his home in Kilburn, North London. Duffy was released, but the Operation Hart computer logged his arrest.

On 17 July, Duffy was called in for questioning by Operation Hart detectives, but arrived with a solicitor and refused to give blood samples. Detectives had a nagging suspicion that Duffy was their man, due to the fact that he fitted the description of the rapist, was short, had pockmarked skin, and had the same laser staring eyes described by so many of the victims. His reference to a martial arts class also struck a chord with detectives, as they remembered the broken bone in the neck of Maartje Tamboezer, and the suggestion that it had been caused by a karate blow. However, with lack of hard evidence, they were unable to detain him and he was released.

Four days later, the body of Anne Lock was discovered by a gang of track maintenance workers on an overgrown embankment near Brookmans Park Railway Station. She had been killed in the now usual fashion, and an attempt had been made to burn her body. The same coarse string was found binding her hands behind her in the “praying” position.

The discovery of her body led detectives to attempt a second interview with Duffy, but to their astonishment they found that he had been admitted to a psychiatric hospital in Friern Barnet, North London. Duffy claimed that he had been assaulted by two men, and had lost his memory as a result. Police were sceptical, but could not disprove his claims. Doctors forbid detectives to question Duffy, and police had to leave him in the security of the hospital. He remained here for a month.

On Tuesday October 21, a 14 yr old schoolgirl was raped on the outskirts of Watford, and during the assault, the girls blindfold slipped and she was able to describe a short, pockmarked man with a dog he called Bruce. This fact was to bear significance later on. Upon learning that he had been released from the psychiatric hospital, Duffy was placed under a tight surveillance. Detectives were now convinced that Duffy was their man, and searched desperately for any evidence that would convict him. Their breakthrough came from an unexpected direction and set a precedent used today.

Professor David Canter was a professor of Applied Psychology at the University of Surrey. He was an expert in Behavioural Science, but had never worked with the police before. At this time, the FBI in the USA had used offender profiling successfully for 10 years, although offender profiling was in its infancy in Britain. FBI Agents John Douglas and Robert K Ressler, of the FBI’s Behavioural Sciences unit, had pioneered it and new developments were occurring frequently due to their research. When he was asked for a profile by police, Professor Canter told them he would need to read every statement, every forensic report made.

He also studied a map of all the attacks in an attempt to find the killer’s “home ground”. Within two weeks Professor Canter had produced a report giving the police 17 pointers towards the character, behaviour and possible location of the killer. What really made this a breakthrough and helped resolve the position profilers hold in today’s society was the fact that 13 of these pointers fitted Duffy exactly. Professor Canter’s pointers are shown below, whilst the matches with Duffy are shown in bold beneath.

THE PSYCHOLOGICAL PROFILE:

1. The killer lived in the Kilburn or Cricklewood areas of London:
   (Duffy lived in Kilburn)

2. The killer was married but had no children:
   (Duffy was married but was infertile, and unable to produce children)

3. The marriage was in serious trouble:
   (Duffy was separated from his wife)

4. The killer was a loner with few friends:
   (Duffy had only 2 close male friends)

5. The killer was a physically small man who felt himself to be unattractive:
   (Duffy was 5”4, and had severe acne)

6. The killer had an interest in Martial Arts or Bodybuilding:
   (Duffy spent much of his time at a Martial Arts club)

7. The killer felt the need to dominate women:
   (Duffy was a violent bully who had already attacked his wife)

8. The killer fantasised about rape and bondage:
   (Duffy liked to tie up his ex wife during sex, and had already raped her)

9. The killer had a fascination for weapons, especially knives and swords:
   (Duffy had many such weapons in his home)

10. The killer indulged his sex and violence fantasies with videos and magazines:
    (Duffy collected hard-core porn and Martial Arts videos)

11. The killer kept a souvenir of his crimes:
    (Duffy had 33 door keys, each taken from a victim as a souvenir)

12. The killer had a semi skilled job as a plumber, carpenter or similar:
    (Duffy worked for British Rail as a carpenter)

13. The killer was in the age range of 20 to 30 years old:
    (Duffy had been a rapist for 4 years when he was arrested aged 28)

When police fed these details into their computer and programmed it to sift through their suspect database and single out suspects fitting this criteria, the computer came out with one name after detectives had cross checked the profile against their 1,999 suspects. The name was John Duffy. On Sunday 23 November 1986, aware that Duffy realised he was being watched, senior detectives ordered his arrest.

Detective’s who searched Duffy’s home found hard-core pornography, Martial Arts videos and magazines, and several Martial Arts weapons. He was also found to have a dog named Bruce, matching the rape victim’s story. It was during a search of his mother’s house that they found a significant breakthrough. Hidden under the stairs was a ball of Somyarn. Forensic experts were able to match this with one used to bind the murder victim’s. Fibres found on Duffy’s clothes matched those recovered from the body of Alison Day. Duffy, throughout all of his questioning, refused to admit anything, even when faced with undeniable evidence, and remained impassive as he was charged with rape and murder.

Duffy betrayed absolutely no emotion at his trial, 14 months later, at the Old Bailey. 7 of his rape victims refused to give evidence against him, so he was tried for 5 rapes only and the 3 murders. Duffy pleaded not guilty to all counts, but was convicted of all the rapes and the murders of Maartje Tamboezer and Alison Day. The prosecution agreed that there was insufficient evidence in the case of Anne Lock and Duffy was acquitted of this murder. Duffy again displayed no emotion as he was sent to prison to serve 8 life sentences. He went to prison taking the name of his accomplice in 16 of the rapes with him.

That was at least, until 2001, when detectives arrested a known associate of John Duffy named David Mulcahy. A routine DNA test matched the DNA left by Duffy’s accomplice and Mulcahy was charged with 16 counts of rape. He pleaded not guilty, but was convicted and sentenced to life imprisonment. To many, that was final closure of the dark times when Duffy and Mulcahy stalked the streets.

John Francis Duffy was born on the 29 November 1958 in Northern Ireland, the second of John and Philomena Duffy’s 3 children. The young Duffy came from a respectable Catholic family, and was a choir and altar boy at the local Catholic Church whilst growing up. He attended St Dominic’s RC School in Kilburn, North London, and, from the age of 12, Haverstock Secondary School. Duffy was a shy child, but enjoyed swimming and judo, and joined the scouts and the Army cadets.

Physical and sporty, his written work was nevertheless poor, and he was advised to seek work learning a trade, “with his hands”. In April 1975, Duffy enrolled as an apprentice carpenter with a firm in Camden, North London. Here Duffy obtained his City and Guilds craft certificate, although he did not make himself popular with his workmates.

He was known as the firm’s top “skiver”, his work was reported as poor, and when he finished his apprentiship in 1978, he was not offered employment by the firm. Duffy spent the next two years working for a London building firm, then in 1980 he joined British Rail.

His work with British Rail taught him an extensive knowledge of the railway system in and around London. It was also around this time that he met his future wife, Margaret Byrne. Both were virgins when they met, and after a short courtship, they were married at Camden register office in June 1980. The couple married in secret because Margaret’s parents disapproved of Duffy, and they did not begin to live together until 3 months after the wedding.

Their marriage was at first happy, until spring 1982, when Duffy learned that he was unable to father a child. Overnight he changed. He resigned from British Rail, attempted suicide, and began to beat Margaret. He personally blamed her for him not being able to father a child, and became convinced that he was ugly and unattractive. In August, she left him. She returned a month later to try and patch up their marriage. Margaret had two jobs to pay the bills, whilst Duffy wasted the days away watching horror and kung fu films.

This sparked an interest in Martial Arts, and Duffy began undertaking a punishing fitness regime. His violent tendencies also came out more as a result, and he now vented his frustrations on Margaret and his pet dog, Bruce. Police theorized that during Duffy’s training sessions he was geographically planning the intricate geometry of his sex attacks and the vital escape routes through London’s railways and Underground network.

It was in August 1985 that Duffy raped his wife. They had been separated for a while by that time. Duffy had also severely beat Margaret’s new boyfriend, and as a result was charged with malicious wounding and assault. These factors only emerged after Duffy’s conviction. Margaret has since remarried and has a son.

Detectives found several urban guerrilla manuals in Duffy’s home after his arrest, all of which listed different ways to incapacitate, silence and kill. The books also stressed the importance of escape routes, a factor that became all important to Duffy. Duffy’s conviction was front-page news in the British tabloids, reflecting the relief that the British public felt at having him behind bars.

Also, the British press opened up the world of Offender Profiling to the British public, and it was largely due to the groundbreaking work produced by Professor Canter in this case that Profiling has become the respected and trusted investigative tool it is today. Professor Canter actually headed a team of experts to research the core of Offender Profiling as a result of its success in the Duffy case, and to adapt it into everyday use.

Little has been written of David Mulcahy, although when Mulcahy was convicted in 2001, this only reinforced the relief that the British public felt. Both men are a natural target in prison, as rapists are despised, and both have been told that they will die in prison. Neither man expects to be released. The names of Duffy and Mulcahy will forever be remembered for their catalogue of horrific crimes, but also as being part of the flagstone that heralded modern Offender Profiling.