I wrote about 70s flashbacks the other day in my newsletter about cults. This week came another blast from the past, with the news that Peter Sutcliffe has died. For those of you who don't remember, he was the Yorkshire Ripper. He murdered 13 women in England in the late 1970s, and had been incarcerated since 1981.

He was one of that particular wave of serial killers of the 70s and 80s (including Ted Bundy, David Berkowitz and John Wayne Gacy), that really shaped the culture for years to come. These guys were perp-walked on color TV. They coincided with the rise of the celebrity age.

The FBI started using the term “serial killer” in the 70s (for the Son of Sam killings), and it became a plotline for movies and TV shows: and a script we're all familiar with, of him being a “white man, 25 to 40, of above average intelligence”. (Even though criminologists will tell you this is not true: serial killers tend to be of below-average intelligence.)

Nor are they particularly charming or attractive. This is acutely obvious when one looks at pictures of Ted Bundy - who was often held up as “the handsome one”. He's only handsome next to David Berkowitz and Charles Manson. He was definitely not Paul Newman.

But the idea of the urbane and intelligent Hannibal Lecter type persists. A genius matching wits with detectives. It’s a model that has haunted murder investigations since the first “serial killer” of the modern time, Jack the Ripper. In the Sutcliffe case, there were direct echoes: letters and recordings sent to the police, purportedly from the killer, adopting the term “ripper”. They turned out to be a hoax.

But the obsession continues. Think of how long people have spent trying to figure out the Zodiac killer’s codes. Rather than making the quick assumption that he was probably - unstable? - and that what he wrote might have been confused nonsense.

In the case of Sutcliffe, he lingered longer than some of his contemporaries, since the UK had abandoned the death penalty in the 1960s. So he spent nearly 40 years incarcerated. He would pop up occasionally in the news, on the anniversaries of his crimes or recently that he'd formed some sort of pen pal relationship with a young woman in America.

He lingered in the freakshow corners of popular culture, a reference point for both horrific violence, and also incompetent policing. The police later issued an apology for their handling of the case, which including paying little attention to the murders of prostitutes, but only snapping to when some “respectable” women became victims.

Several years ago I reviewed Christine Pelisek’s fascinating and horrifying book The Grim Sleeper, which detailed her dogged coverage of serial murders in South Central Los Angeles (as a journalist for LA Weekly). There too, victims had primarily been prostitutes, who tended not to get either media or police concern. Years of unsolved killings culminated in the horrific realisation for detectives that there was not one serial killer operating - but SIX, independent of each other. The Grim Sleeper was finally caught by DNA testing, a familial match only possible because his son had an unrelated felony charge and was in the system. If not for that connection he wouldn’t have been found.

Serial killers like this haven’t hit the news much lately, and I really don't know if that's because patterns of offending have changed so much. Or just that some would-be serial killers being caught sooner. That well before they get to victim number 12, they have been arrested tracked down by DNA surveillance. Perhaps our technology of policing and panopticon state is catching people earlier in what would have been their career of crime. But it’s hard to speculate, or be too confident.

Society did respond to the serial killer phenomenon by seeing danger everywhere. One obvious example is the decline of hitchhiking (these days anyone shown in a movie hitching a ride is bound to show up dead in a ditch ten minutes later).

Graeme Chesters and David Smith suggested in a 2001 article that hitchhiking (in Europe and the US) started falling from popularity in the 70s. There seem to have been a combination of factors, though the one most people would point to is perceived risk. Indeed, some well-publicized crimes (such as the Santa Rosa murders in California), were certainly a contributing factor. There were also changes in road laws (hitching was banned on many major highways), and increased vehicle ownership - so fewer people needed to hitch.

But as suggested at Freakonomics, it becomes a bit of a vicious cycle: as fewer “normal” people either hitch, or pick up hitchhikers, the more it is seen as an activity for marginal and possibly dangerous individuals. I've certainly never hitchhiked. I grew up in the era of Stranger Danger, which was partly driven by this serial killer fear.

We now have electronic hitchhiking (with Uber and Lyft), and kid ourselves that these are a safer option than just sticking our thumb out and taking a chance. Of course we’d only take a ride with someone we know and trust. The most haunting detail of the Sutcliffe case, that has stuck with me since I heard it years ago, was that a female coworker of his got him to drive her home from the office: since she had heard there was a murderer at large.