Why did this particular case unleash a hellish legion of voyeurs and amateur detectives? What was it about the disappearance of a very ordinary woman from the small town of St Michael on Wye that was so different? After all, people go missing every day and few make the headlines.

First of all Nicola Bulley was a ‘worthy victim’, a photogenic woman with a young family. Had a young man gone missing near the River Wye, I doubt there would have been much public interest. Second, the circumstances of her disappearance were dramatic – with the abandoned family dog and her mobile phone left on a bench, it was as if she had been spirited away.

Lastly, we live in a time of raised concern for women’s safety. There is little evidence that this is justified, but statistics don’t count in the face of moral panic. Accordingly, the obvious explanation, that she had gone into the nearby river, was dismissed as too simple. It didn’t play to the conspiracist mindset.

It is a source of dread for any police investigator that their case will become the focus of conspiracy theories and media intrusion. It adds to the anxiety of the victim’s families and it can seriously impede an investigation. “A distraction and a damned nuisance” as a dear old boss of mine used to say. The problem is that all leads, no matter how spurious, must be bottomed out. Public assistance is essential, public obsession is a vexation.

And while police/press relations are usually manageable, social media is another matter. The internet is a perfect incubator for conspiracy theories, while the deluge of true crime TV shows convince some that they possess the investigative skills to outmatch the professionals. But social media cannot be blamed entirely for this all-too-human phenomenon.

Recently, I have been writing about another case where a small town was inundated by a mob of prurient conspiracists, amateur sleuths, and worse. It happened in 1935 in the small border town of Moffat when two dismembered corpses were found dumped in a ravine north of the town. The press went into overdrive and, by the next day, hundreds of people had made their way to the remote area to exercise the skills they had gleaned from Agatha Christie’s novels. Amateur detectives, opportunists, oddballs and voyeurs thronged to the town, all driven by the same determination to be part of the drama.

The morbid fascination with what became known as “the Ruxton Murders” happened nearly 90 years ago, before the time of television and when the internet was beyond imagination. It seems little has changed.

The disappearance of Nicola Bulley, whose body was eventually found in a river near her home, was the subject of huge public interest (Picture: Danny Lawson/PA)

In a worrying footnote, the public’s obsession with the Ruxton Murders continued and the families of the victims were mercilessly trolled and abused for years. Let’s hope history does not repeat itself and that the family of Nicola Bulley is now left in peace.

Tom Wood is a former police officer and author of the book, Ruxton: The First Modern Murder

Nicola Bulley's disappearance unleashed a hellish legion of conspiracy theorists and amateur sleuths. Something similar happened 90 years ago in Moffat – Tom Wood