David John Birnie was born in 1951 to Margaret and John Birnie. He was the oldest of six children. Margaret and John were both alcoholics who had a great deal of trouble raising their children due to the family’s low income. The children were periodically removed from the household by social services when Margaret and John were unable to afford them. When his parents divorced, neither wanted custody of David and he became a ward of the court.
Catherine was born in 1951. Her mother passed away when she was only 10 months old. She was sent to South Africa to live with her father; he sent her back to Australia two years later to live with her grandparents. Approximately one year later, she was sent to live with her aunt and uncle. She was a very sad child and did not have any friends. Many of the neighborhood children had been forbade by their parents to associate with her. She felt very lonely and rejected and possessed a strong desire to be loved. David and Catherine met as children; their parents lived next to each other.
The two were reunited in their late teens. By that time, David had spent much of his life in juvenile detention halls. He and Catherine embarked on a crime spree. On June 11, 1969, they were charged with eleven counts of theft and breaking and entering. David was sentenced to nine months in prison. Catherine was pregnant at the time and only received probation. The following month, the two appeared before the Supreme Court, charged with another eight counts of theft. Three more years of imprisonment were added on to David’s sentence and Catherine received an additional four years of probation.
On July 21, 1970, David escaped from Karnet prison and reunited with Catherine again. It was not long before the two were once again in trouble with the law. They were arrested on July 10, 1970 and charged with 53 counts of theft, breaking and entering, trespassing and illegal operation of a motor vehicle. In their possession, police found wigs, radios, dynamite, detonators and fuses. Catherine admitted to knowing that her actions were wrong, but claimed that she loved David and would do absolutely anything for him. David was sentenced to two and a half years in prison and Catherine was sentenced to 6 months of imprisonment. Her baby was taken by welfare services.
Upon her release from prison, Catherine found work as a live-in servant in Fremantle. She fell in love with a young man named Donald McLaughlan, the son of her employers. They married on her 21st birthday, May 31, 1972. Soon after, Catherine gave birth to their first child. Unfortunately, the baby died at only 7 months old after being struck by a moving vehicle. Catherine witnessed the accident. Over the years, the couple had five more children and their marriage began to sour. Catherine did not take care of her house or her family. She found herself missing David.
She left her husband and children to move in with David. They were never officially married, but she had her surname changed to his and became his common-law wife. David had an unquenchable sexual appetite and the couple began considering abducting and raping young women to add zest to their sex life. They realized their shared fantasy in October of 1986; that is when the killing began.
By November 5, 1986, Detective Sergeant Paul Ferguson became convinced that a serial killer was on the loose. Denise Brown was the fourth person to be reported missing in a span of 27 days. It struck him as odd that two of the missing persons had made contact with family/friends after being reported missing. Chief Bill Neilson agreed with the serial killer theory and the two began their investigation. The detectives would receive their big break only five days later.
On November 10, 1986, a 17-year-old girl ran into a local supermarket. She was half-naked and hysterical, but managed to announce that she had been raped. She was taken to the police station, where she told her story of survival. She said that she was abducted and held at knifepoint by a couple that had asked her for directions. She recalled being taken to a house where she was stripped and chained to the bed. The male raped her as the female watched. The following morning, she was alone in the house with the female, the male had left for work. She pleaded for the woman to unchain her; much to her amazement, the woman complied. The woman forced her to call her family and tell them that she was visiting with some friends. When the female accomplice left to answer the door, the girl escaped out of the open window in the bedroom.
Despite her harrowing ordeal, the girl was very intelligent and managed to remain alert. She was able to provide police officers with the address and phone number of the couple. She led police to the house, where they hid outside in a parked van. When Catherine returned home, she was immediately arrested. She told police where to find David, who was then arrested. The couple denied the accusations against them and claimed that the young girl had consented to sexual intercourse. In the house, police found a pocketbook and pack of cigarettes that the young lady was smart enough to hide there.
Police were still in need of a confession, since there was no concrete evidence against the couple; it was their word against the girl’s. The couple was interrogated separately. This is a common police tactic. If interviewed together, the two would influence and corroborate one another’s story. If separated, the bond between them is temporarily broken and the likelihood of a confession is greater. The tactic worked and David admitted to committing the murders. His confession prompted Catherine to confess as well.
The couple led police to the burial sites of the four victims. David and Catherine were formally charged with the four murders on November 12, 1986. The trial took place on March 3, 1987 and only lasted a half hour. Both received life imprisonment without the possibility of parole for a minimum of twenty years. David was sent to Casuarina prison and Catherine was sent to Bandyup prison. The two kept in touch for several years. In February 2005, a man received a large settlement after claiming that he was raped by Birnie while imprisoned at Casaurina. On October 7, 2005, David committed suicide, hanging himself in prison. His body remained in the morgue for over a month because no one was willing to claim it. He was given a covert funeral on November 21, 2005.