ABC Science journalist Sana Qadar starts her video with a question that feels simple until you sit with it for a minute. Ted Bundy, Jeffrey Dahmer, John Wayne Gacy, and Ivan Milat are still names people recognize decades later. But when was the last time the news was full of an active serial killer stalking suburbs, highways, or rural back roads?
For many people, the answer is either “a very long time ago” or “never.” That is the mystery Qadar set out to explore in her All in the Mind report on criminal psychology. And her conclusion is not that serial killers are gone, exactly, but that their numbers have dropped sharply, and for more than one reason.
The most obvious answer, she says, is better policing. DNA science improved. Surveillance improved. Investigators got better at connecting crimes. Those things matter, and they probably explain a good part of the drop.
But Qadar’s report goes further than that. She looks at psychology, environmental theories like lead exposure, controversial ideas about abortion and crime, and the changing social habits that may have made it much harder for serial killers to find victims in the first place.
It is a fascinating topic because serial killers once felt like a permanent part of public fear. Now they feel more like a dark relic of another era, even if the truth is not quite that clean.
Sana Qadar Says The Peak Came Decades Ago
To understand the decline, Qadar says you have to go back to the 1970s. In her telling, that decade was not just disco, flared pants, and social upheaval. It was also a period when serial killers seemed to be everywhere.
She notes that the yearly average number of serial killers in the United States exploded in the 1970s and peaked in 1987. Since then, the pattern has been downward.
Importantly, she says this is not just an American story. The same broad drop shows up in the United Kingdom and in Australia too.
That matters because it suggests something bigger than one country’s policing style or one legal system’s quirks. When the trend appears across multiple Western countries, it starts to look more like a broad social shift.
Qadar does not treat that decline as a mystery with one neat answer. Instead, she builds her report around the idea that several forces may be working at once.
That feels like the right way to approach it. Human violence rarely rises or falls for one reason only, and serial killing is probably no different.
The Psychology Has Not Changed, But The Opportunity Might Have
Before getting into theories about falling numbers, Qadar first lays out the psychological basics. She says two things are important in a serial killer’s makeup.
One is a lack of empathy. The other is a desire to kill.
That desire can come from different places. Some people kill for money, like a hitman. Others do it for thrill, power, or sexual gratification. Qadar says that in around half of all serial killings, the urge is driven by sexual fantasies.
She also notes that research has found many serial killers with this kind of sexual motivation begin enacting violence very young, often in their teenage years.
That is one reason better policing matters so much in her report. If people with violent patterns are being identified earlier, then some may be caught after an initial violent crime before they ever have the chance to become serial killers in the classic sense.
This is one of the strongest parts of Qadar’s argument. It does not require society to believe there are no longer people with these urges. It only requires the system to be better at spotting and stopping them earlier.
And that seems plausible. The modern world leaves more traces. More cameras, more records, more forensic tools, more chances to get caught.
A killer who might once have moved through several crimes before police connected the dots may now run into the wall of evidence much faster.
The Lead Theory Is Compelling, But It Is Still Just A Theory
One of the more surprising angles in Qadar’s report is the “lead crime hypothesis.” Back in the day, she explains, lead was in petrol, water pipes, paint, and all over the environment. In Australia, she notes, leaded petrol was not banned nationwide until 2002.
She says childhood lead exposure has been linked to aggression and antisocial behavior. The theory is that as lead was phased out, children stopped being exposed to one major factor that may have contributed to later violent behavior, and as a result, violent crime fell.
Qadar points out that the homicide rate in the United States has dropped dramatically since the 1980s, and some people see lead exposure as part of that story.
It is a compelling theory because it tries to explain not just serial killers, but a broader decline in violent crime. And there is something unsettling about the possibility that an environmental toxin may have helped poison not just bodies, but behavior.
Still, she is careful not to oversell it. Qadar says experts are split on how much lead really explains. She also notes that one group of researchers found publication bias in this area, meaning studies that showed a strong link were more likely to be published than studies that did not.
That is an important caution. The theory may explain something, but it may not explain as much as people want it to.
And that is a theme throughout her report. Serial killers likely did not disappear because of one dramatic breakthrough. The drop may be the product of many smaller forces, some proven and some still debated.
The Abortion-Crime Theory Gets Raised, But Rajan Darjee Treats It Carefully
Qadar also brings up the Donohue-Levitt hypothesis, popularized by Freakonomics, which argues that legalized abortion may reduce crime by reducing the number of unwanted children born into very difficult situations.
It is one of those theories that always draws attention because it is provocative and because it sounds like it explains a large social trend with one policy change.
But Qadar is clearly not presenting it as settled truth. She says there are real doubts about whether it holds up.
To help sort through that, she speaks with Dr. Rajan Darjee, a consultant forensic psychiatrist. Darjee says the theory is plausible as a contributing factor, but only as one factor among many.
He compares it to the lead theory and says that even if abortion availability contributed to lower crime, it likely did so only a little. Darjee also makes a very grounded point: plenty of children who are wanted are still mistreated or born into highly disadvantaged settings.
That response helps deflate the temptation to turn one complicated social trend into one tidy explanation. Qadar seems interested in theories, but she is also careful to show their limits.
That gives the report more credibility. Too much true-crime coverage likes certainty where none really exists. This piece is stronger because it leaves room for doubt.
Everyday Life Changed, And That May Have Made Victims Harder To Reach
After looking at those larger theories, Qadar turns to something much simpler. Society changed in ordinary ways.
People are more likely to lock their doors. They are less likely to hitchhike. Child protection services improved. Those may sound like small changes, but Qadar argues they made it harder for predators to find easy victims.
That point feels especially important because a lot of notorious serial killers did not just rely on cruelty or cunning. They relied on opportunity.
A world with more unlocked doors, more isolated kids, more hitchhiking, less scrutiny, and looser systems gave predators more room to operate. Tighten those gaps a little, and some of that opportunity disappears.
This may be the least flashy explanation in Qadar’s report, but it may also be one of the most convincing. Crime often depends on access. If society becomes harder to move through invisibly, some crimes become harder to repeat.
That does not mean danger is gone. It just means the conditions that once helped serial killers thrive are not as common as they used to be.
Chemical Castration And Treatment Raise A More Controversial Question
Qadar also explores one of the more controversial reasons serious violent sexual offenders may reoffend less often: treatment, including what is commonly called chemical castration.
She notes that some rehabilitation programs include long-term psychological therapy, but also injectable anti-libidinal medications that reduce testosterone levels and, as a result, reduce sexual fantasies and urges.
In cases where sexual fantasy is part of the motivation to kill, that matters. Qadar says that by cutting down those fantasies, you cut down one of the drivers behind the violence.
But again, the report does not treat this like a magic fix. Darjee says reducing recidivism among violent sex offenders usually requires a combination of psychological treatment, pharmacological treatment, supervision, and ongoing monitoring.
He also says some people are simply never going to be safe to release.
That is a sober but necessary point. Treatments may reduce risk, but they do not erase history or guarantee safety. And in the case of people who have committed multiple homicides, the stakes are obviously too high for wishful thinking.
Still, Qadar includes this angle because it shows one more way the world changed. Society now has more tools not only to catch violent offenders, but to manage and monitor some of them after conviction.
Serial Killers Have Not Vanished Completely
For all the evidence of decline, Qadar is careful not to say serial killers are gone. She says there may not be any active serial killer cases in the news right now, but that does not mean such offenders are not still out there.
Some, she notes, can take years to identify.
She points to Bradley Edwards, the Claremont killer, as an example. Edwards was convicted in 2020, but his crimes largely happened in the mid-1990s. He killed Jane Rimmer and Ciara Glennon and was also suspected in the murder of Sarah Spiers, whose body was never found.
His case dragged on for decades before a DNA breakthrough led to his arrest in 2016. That alone is a reminder that the absence of headlines is not the same as the absence of offenders.
Qadar also cites a criminologist who estimated there could be one or two active serial killers in Australia right now whose patterns simply have not yet been recognized.
That is a chilling possibility, and she follows it with an even more uncomfortable thought: they may be targeting people society is quicker to overlook.
Some Victims Still Receive Less Attention Than Others
That leads Qadar into one of the most powerful sections of the report, where criminologist Xanthé Mallett talks about vulnerable victims.
Mallett says people suffering homelessness, drug or alcohol dependence, sex workers, and Indigenous women can be especially vulnerable. She adds that society values some lives differently from others.
Qadar connects that point to the Bowraville murders in New South Wales, where three Indigenous children under 16 were murdered over five months in 1990 after disappearing from parties on the same street.
Mallett’s point is harsh and hard to ignore. She says if those had been three “little Caucasian children” from Sydney’s eastern suburbs, the story would likely have made headlines around the world.
Instead, Qadar says detectives struggled to get media interest, and local police initially suggested some of the children had simply “gone walkabout.” A local man was later charged with two of the murders, then acquitted. No one has ever been convicted.
This is where the report becomes about more than serial killers. It becomes about visibility.
Serial killers may seem to have vanished in part because some of the victims who remain most vulnerable are still the ones least likely to generate national panic. That is a deeply uncomfortable thought, but Qadar does not shy away from it.
And she should not. The story of declining serial killers is not just about better science and safer suburbs. It is also about who gets protected, who gets noticed, and whose disappearance is treated as urgent.
The Headlines Faded, But The Obsession Never Did
By the end, Qadar’s answer is clear enough: serial killers have not completely disappeared, but their numbers have fallen over the last 60 years.
Better DNA science, stronger policing, improved surveillance, social changes, treatment of violent offenders, and perhaps broader environmental shifts all seem to be part of the story. Some theories look stronger than others. Some remain unresolved.
What has not dropped, she notes, is our obsession with serial killers. Culture is still drawn to them, still trying to understand their minds, still willing to watch and read and listen.
That may be why this subject still grips people so strongly. Serial killers once felt like a constant feature of modern fear. Now they feel rarer, stranger, almost like a species fading from view.
But as Sana Qadar makes clear, rarer does not mean gone. And quieter headlines do not always mean a safer world for everyone.
Mark grew up in the heart of Texas, where tornadoes and extreme weather were a part of life. His early experiences sparked a fascination with emergency preparedness and homesteading. A father of three, Mark is dedicated to teaching families how to be self-sufficient, with a focus on food storage, DIY projects, and energy independence. His writing empowers everyday people to take small steps toward greater self-reliance without feeling overwhelmed.
