A couple of days before Christmas 2015, Russell Findlay, a Sun journalist, answered his front door to a man dressed in a postman’s uniform who handed him a pen. As the reporter reached out to accept it he was blinded by a splash of cold liquid across his face.

The fake postman, having doused Findlay with sulphuric acid, then lunged at his victim. Findlay instinctively fought him off and the attacker tried to flee to his getaway car. Despite his burning face and stinging right eye, Findlay jumped on his back and wrestled him to the ground. Neighbours joined in. The police arrived and the man was arrested. His six-inch knife was found near the front door.

More than a year later, Findlay’s assailant, William Burns, a Glaswegian with a string of convictions, was sentenced to 15 years: a 10-year jail term plus five years’ post-release supervision.

Thankfully, Findlay’s sight was saved. His skin has since recovered. The story, as told in his new book, Acid Attack: a journalist’s war with organised crime, has cast light on the reality of Glasgow’s vicious gang culture and the dangers for those brave enough to report on it.

His experience also opens up disturbing questions about the way he was treated by his newspaper.

Informing the public about organised crime, which inevitably means getting under the skin of people who live by violence, has often proved perilous for journalists. In 1996, Irish journalist Veronica Guerin, who had reported extensively on drug dealing by Dublin gangs, was shot dead. She had narrowly avoided a previous murder attempt and had received several death threats. In 2001, Martin O’Hagan, a reporter with the Sunday World in Northern Ireland who had exposed drug dealing by a loyalist paramilitary gang, was shot dead. He had also been threatened several times.

What links the cases of Findlay, Guerin and O’Hagan – apart from their refusal to back down in the face of intimidation – is the unchecked influence of gangsterism. In Glasgow, Dublin, Belfast and County Derry, gangs hold sway. The forces of law and order have failed to bring them to heel. By contrast, the days of high-profile gangsters in London, such as the Krays and Richardsons, vanished long ago.

It reminds me that their regimes of fear followed an era in which a journalist of the 1940s and 50s, Duncan Webb of The People, survived several beatings while reporting on the activities of gangs in Soho. He became famous after exposing the five Messina brothers responsible for trafficking women from Europe to work as prostitutes. They had thumbed their noses at the police and courts. Immediately after his first report was published, they fled Britain.

Webb continued to report on gangs that ran protection rackets in order to finance robberies, and he made much of his need to protect himself, claiming that his front door was fitted with eight locks, he worked from an office with bullet-proof glass and often slept at a different address every night. His editor, Sam Campbell, provided him with minders and was willing to overlook the fact that Webb made a potentially compromising deal with one gangster, even ghost-writing his autobiography, to act as his source. One key reason for Webb’s successful career, which ended only because of his death aged 41 due to an inherited medical problem, was the close relationship he had with Campbell.

Although film and TV portrayals of reporters too often make them out to be intrepid lone wolves, the reality is very different. They depend on support from their editors and colleagues. Newspapers are a collective after all.

And it is that aspect of Findlay’s tale that is worrying. He relates how the then editor of the Scottish Sun, Gordon Smart, failed to tell him about a phone call from a criminal who had threatened to do him harm. Moreover, the caller boasted that he knew Findlay’s address, his car registration number and other personal details.

The call, from a man believed to have orchestrated the assault on Findlay, was made some 10 months before the attack. But Smart did not reveal it to his reporter until he visited the paper’s office days after leaving hospital. “I couldn’t believe he kept it from me,” said Findlay.

Once he knew about it, he demanded that Smart tell the police, who were investigating the attack. The editor then gave a statement to detectives about the incident at a meeting attended by a lawyer acting for the Sun’s publisher, News UK.

Although Findlay later returned to work, he soon went on sick leave and never returned to the newspaper, leaving on medical grounds. As for Smart, he was suddenly plucked from Glasgow to become the Sun’s deputy editor in London, lasting just six months in the post until he resigned in November 2016 to pursue a broadcasting career.

So why did he withhold the information from Findlay? In his book, Findlay writes: “I am certain there was no malice on his part. The only conclusion that made any sense was that he had not viewed the call as a serious threat.”

It would appear that Findlay’s hunch is broadly correct. I understand that Smart, while conceding that the threats against Findlay were made during what was a lengthy phone call, was also threatened himself.

Smart viewed the conversation in the context of such threats against journalists often being made by the city’s gangsters. Evidently, he did not believe the call to be of sufficient significance to inform Findlay.

Smart’s colleagues point out that, in the wake of the attack on Findlay, he contacted other Scottish newspaper editors to ensure that there was a unified stand on behalf of his reporter.

It is also the case, as Findlay readily agrees, that he received support from News UK’s chief executive, Rebekah Brooks, who was very concerned and sympathetic, both for Findlay and for his daughter, then aged 10, who witnessed the attack.

Smart told me that the attack was “deeply upsetting for Russell and it is great that he was shining a light on criminal activity in such a brave way”. His own decision to resign from the Sun had nothing whatsoever to do with the way he handled the Findlay case.

A News UK spokesperson reiterated that the London-based company had dealt properly with the matter, saying: “Journalism often means you are dealing with challenging environments and the safety and security of our staff is paramount. We have strong and robust structures in place to respond to such an incident. The hallmark of Russell Findlay’s career is brave reporting where many journalists would fear to tread and we are sorry he chose to leave the Scottish Sun.”

Taking all that on board, it’s hard to escape the conclusions that Findlay did not receive, at least in his own office, the appropriate duty of care he deserved from his employer. Worse, surely, is the message that Findlay’s treatment, leading to his resignation, implies to Glasgow’s gangsters: there is a way to make inquiring journalists back off.