As creative and industrious as the investigative team working on the Golden State Killer case were in the end, the sad truth is that Joseph James DeAngelo should have been arrested almost 40 years ago.

The glaring omission is the only tangible opportunity any of the authorities had in trying to stop the spree of sadistic cruelty that earned him the villainous title of the worst unidentified violent serial offender in modern American history.

Joseph DeAngelo, the Golden State Killer. Picture: 60 Minutes (60 Minutes)

But the bungle also shows that despite the best DNA data bases and advances in sample analysis, it’s human error and lapses in judgement that will always have the greatest impact on crime prevention.

Let me explain.

It was toward the end of 1979 and DeAngelo was working as a sworn officer for the Auburn Police Department in Sacramento.

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The station is about a thirty-minute drive to his home and sits within a similar distance to various houses where attacks were carried out by the ‘East Area Rapist’.

That moniker had been splashed all around the region, across newspapers and television screens for months on end and if you lived in any of the adjoining suburbs, you would have been hard-pressed not to have discussed it with friends or neighbours because the number of victims was simply staggering.

DeAngelo pictured in his police uniform. Picture: 60 Minutes (60 Minutes)

The first rape was in 1976, not long after DeAngelo began as a policeman at Auburn and by the time he walked into a Pay N’ Save store in nearby Citrus Heights on a sunny day, three years later, the East Area Rapist had chalked up the grim total of 44 vicious rapes.

There were also two murders but detectives were still some twenty years out from connecting all the dots.

DeAngelo, however, had already decided that he was above the law, moving to a back shelf that day and helping himself to a hammer and a can of dog repellent.

It could have been a slip in concentration or just a show of arrogance but he didn’t count on an observant shop assistant and was promptly caught and charged.

A jury found him guilty of misdemeanour shoplifting and he was fined $100 and given six months’ probation.

DeAngelo earned the title of the worst unidentified serial offender in modern US history. Picture: 60 Minutes (60 Minutes)

Detective Paul Holes. Picture: 9NEWS (60 Minutes)

But here’s the best bit. His Chief of Police at the local station fired him for conduct unbecoming – clearly, he wasn’t fit to wear a police uniform – and sent him on his way.

He said DeAngelo was angry, they had words and he offered some threats but didn’t take any of them seriously.

A few nights later, the Chief was woken at his home by his young daughter who fearfully explained there was a man outside her bedroom window with a torch.

The Chief later told detectives working the case that he found footprints the next morning and was convinced it was a vengeful DeAngelo trying to put a scare into him.

With the passing of time, it’s difficult to tell if the Chief was simply incompetent or blindly naïve or maybe a bit of both.

Listening to a haunting recording of the Golden State Killer with Mrs Wardlow. Picture: 60 Minutes (60 Minutes)

Mrs Wardlow pictured as a young girl. Picture: 60 Minutes (60 Minutes)

With so many unsolved rapes outstanding in surrounding areas, a man stealing such items seems suspicious enough but throw in a police uniform and a nocturnal visit outside a child’s bedroom and you would think you have the ingredients for something much more sinister?

At the very least a reason to question your ex-employee at some length and perhaps even a search of his home?

But no, incredibly this chief of police chose to do nothing.

Was he worried about embarrassment to his own brothers-in-arms and how it would reflect on his leadership? Perhaps.

But we now know that at least another six women would be raped and eleven people murdered in the months and years that followed and for me, the bigger question is could their lives have been saved?

Remember, at the time DeAngelo shoplifted these highly suspicious items, there were several other serial rapists operating in the area.

Margaret Wardlow was one of DeAngelo's youngest victims. Picture: 60 Minutes. (60 Minutes)

Jane Carson was brutally raped by DeAngelo. Picture: 60 Minutes (60 Minutes)

There was the Vampire of Sacramento, who killed, cannibalized and drank the blood of some of his six victims and there was the Bedroom Basher who raped and bludgeoned five women to death in Orange County.

Although many small police stations operated in silos and had poor communications, it still beggar’s belief that, even in isolation, this police chief would not act further to solve the mystery of why one of his men would want to steal such things.

Surely all those high-profile, unsolved rape cases were discussed at officer level over a doughnut and a coffee?

Conversely, it’s completely understandable that DeAngelo’s suspected burglary spree prior to joining Auburn station was not connected.

DeAngelo is a former police officer. Picture: 60 Minutes (60 Minutes)

Carol Day spoke to 60 Minutes about her ordeal. Picture: 60 Minutes (60 Minutes)

In 1975, he was an officer in Visalia, almost three hours from Auburn when a rash of break and enters were committed by a burglar who liked to take trophies from homes.

He and his police comrades dubbed it the ‘Visalia Ransacker’ but computer networks were so rudimentary that it’s doubtful any local Sacramento stations would have been remotely aware.

It was 2001 before data-bases were suitably sophisticated and more importantly, detectives happened along who were curious enough to notice similarities and make the link.

DeAngelo faces court in an orange jumpsuit. Picture: 60 Minutes (60 Minutes)

The sad truth is that Joseph James DeAngelo should have been arrested almost 40 years ago. Picture: 60 Minutes (60 Minutes)

That’s when it was discovered that over all those years, investigators around the state who had been searching variously for the Cordova cat burglar, the Visalia Ransacker, the East Area rapist, the Original Night Stalker and the Diamond Knot killer realised it was the work of a single perpetrator; The Golden State Killer.

In the end, the inventiveness of a fake profile on a genealogy website means DeAngelo is sitting in a cell, awaiting his fate but was it a change in technology that led to his undoing or was it a change in luck?

Maybe, like the Son of Sam, who was caught off a parking ticket, his luck simply ran out.