On June 29, the Organisation for the Prohibition of Chemical Weapons (OPCW) published a comprehensive report confirming that the nerve agent used in the Syrian regime's April 4 attack on Khan Sheikhoun that killed 92 was sarin. The conclusion was no surprise. The World Health Organisation (WHO) and Doctors Without Borders (known by its French initials, MSF) had already found the symptoms of the victims consistent with exposure to a nerve agent. In a separate analysis, the French government had matched sarin samples from the site to regime stock. A Human Rights Watch investigation also found the regime responsible for this and three other chemical attacks since December, and said the latest attack was "part of a broader pattern of Syrian government forces' use of chemical weapons".

However, the response from the regime and its supporters followed a familiar pattern. There was denial, deflection and deception. There were conspiracy theories. There was whataboutery. But effluvia from this dung heap merely fouled the air until it was ignited into a noxious fire by an inveterate pyromaniac. Enter Seymour Hersh.

Seymour Hersh, a once celebrated journalist, has been reluctant to cede the limelight. But the pride of place that he earned through hard work he now wants to keep by trading on his legacy alone. Hersh, who once did the legwork for his stories - finding sources, corroborating claims, verifying evidence - is now relying on the uncorroborated claims of anonymous sources to tell tall tales that contradict available evidence. The man who broke world-changing stories from My Lai to Abu Ghraib now hops from publication to publication, writing sensational drivel, sullying his reputation and diminishing his publishers'.

His latest story, published in the German daily Die Welt, was a colourful rendition of an extant conspiracy theory: that the deaths in Khan Sheikhoun did not result from a chemical attack but were caused by toxic discharge from a conventional attack on a jihadi facility. Based on the baroque testimony of an anonymous source, Hersh concludes that there was no sarin involved.

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The OPCW report put an end to this nonsense. But more embarrassingly, Hersh's claims were contradicted even by the regime and Russia. His publisher, Die Welt, was left with egg on its face - much like the London Review of Books before, which had published his earlier forays into conspiracism (To its credit, the LRB declined to publish Hersh's latest).

This opprobrium is richly merited - but is it sufficient to discourage others from yielding to the click bait temptation?

For Die Welt to prove that it wasn't deliberately deceiving its audience, it will have to not just retract the story and apologise, it will also have to identify Hersh's anonymous source.

Every publisher knows that conspiracism pays. Some of the internet's most visited sites traffic in conspiracy theories. Conspiracism flatters anti-establishment cynics by providing them with an adversarial posture, diluted of content but full of sound and fury. With the rise of populism, there is a vast reservoir of anti-establishment sentiment to be exploited. And with ad revenues increasingly tied to clicks, even respectable publications appear eager to tap into this pool. Hersh is useful because, regardless of the quality of his work, his oversized reputation allows them to access this resource without suffering much in the way of reputation.

A diligent editor could not have missed all the red flags raised by Hersh's recent stories. Both publications allowed Hersh to bring his own fact checkers, which is astonishingly cavalier considering the incendiary nature of his claims. But the notion was reduced to farce when Hersh used Scott Ritter as his fact-checker.

A one time UN weapons inspector whose reputation was built on his opposition to the Iraq war, Ritter has tried to deal with his recent loss of reputation (over personal indiscretions) by trying to build an audience on the conspiracist fringe. Since his release from prison, Ritter has shown a peculiar set of concerns, marking his return with an attack on the Syrian White Helmets. The attack was shoddy, much of it echoing extant conspiracy theories published on the alt-right conspiracy site 21stCenturyWire (an offshoot of Infowars). But it coincided with the Russian media's relentless campaign against the White Helmets aimed at denying them the Nobel Peace Prize. In subsequent articles, Ritter praised Trump for his overtures to Russia; cast doubt on intelligence reports about Russian hacking of the DNC; and credited Trump's claim that he was being wiretapped by the Obama administration.

But it's what came next that provides clues as to Hersh's source for his latest story and Die Welt's dereliction.

On April 9, Ritter wrote an article based on Russian claims that debuted the conspiracy theory that would later be embellished into the Die Welt article. After repeating the accusation that the deaths in Khan Sheikhoun were caused by the regime's targeting of an al-Qaeda facility, Ritter went on to casually blame the August 2013 Ghouta chemical attack on al-Qaeda and declared the White Helmets their accomplices. Two days later, Ritter signed an open letter to Trump with a group calling itself Veteran Intelligence Professionals for Sanity (VIPS) repeating the allegation, but citing as their source "Our US Army contacts". There is reason to doubt the existence of these "Army contacts".

In 2013, VIPS had written a similar open letter to Obama claiming that according to "numerous sources in the Middle East" the regime was innocent of the Ghouta chemical attack. Except, the article - including the reference to "numerous sources in the Middle East" - was plagiarised from the Canadian conspiracy site Globalresearch.ca. One signatory to this 2013 letter, former CIA officer Larry Johnson, is widely believed to be Hersh's source for his three LRB articles on Syria and bin Laden. Hersh has often relied on the VIPS for his stories. The group, made up of disgruntled former employees of the government, is also the likely source for his current article. In other words: the likely source for Hersh's "facts" was also his "fact checker".

Wittingly or not, it is by now clear that Hersh - and by extension Die Welt - served as a conduit for disinformation. For Die Welt to prove that it wasn't deliberately deceiving its audience, it will have to not just retract the story and apologise, it will also have to identify Hersh's anonymous source. There is no ethical justification for granting anonymity to someone who has deliberately tried to deceive.

Only by exposing such sources to public scrutiny will the press be able to discourage malicious parties from abusing confidentiality principles to advance dubious agendas.

Muhammad Idrees Ahmad is Lecturer in Digital Journalism at the University of Stirling. He is a contributing editor at the Los Angeles Review of Books.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.