A little over 40 years ago Ronald Haeberle walked into the offices of the Plain Dealer newspaper in Cleveland, Ohio, clutching a set of pictures that were to change history. He held in his hands photographs of people's bodies lying in the dirt of Vietnam who had been killed by US soldiers.
On the 16 March 1968 more than 500 men, women, children and babies were murdered in the village of My Lai and surrounding areas, but it was not until 1969 that news of this came to light following an investigation by the journalist Seymour Hersh. The inquiry that followed resulted in the court martial in 1970-71 of Lieutenant William Calley - a member of Charlie Company who was tried and convicted of murdering 22 "Oriental human beings" in My Lai on that morning in 1968.
Behind closed doors an internal army investigation in to the massacre revealed the true extent of the operation that involved two companies: Bravo and Charlie. Both received orders from their commanding officers, permitting them "to kill everything and anything".
Until now it has always been accepted that US Army photographer Haeberle did not photograph any of the actual shooting, he focused his lenses on the dead and those about to die.
Haeberle carried two cameras with him that day, one was an army camera and with it he was charged with photographing the mission to obtain pictures that would be used in the US press to say to the public "here's what we accomplished"; the other was his personal camera.
It was this one that contained a roll of colour-slide film which he used to record the day. He processed the film himself on his return to the US a couple of weeks after the events in My Lai. The film included pictures that, as he puts it, show "smoke coming from the muzzle".
In a recent interview with the Plain Dealer, Haeberle now admits that he did indeed take pictures of some of those doing the killing but later destroyed them. He said: "There are some photographs that after I arrived home [in the US] I realised that there is no way I can release photographs showing who the actual persons are doing what. I figured I'm not going to point my finger at any one soldier. I'm there. I'm part of it. I'm as guilty as anybody else, not for shooting a person, but for not reporting it... it's like one big cover up. There are photographs I could have pinpointed who did what."
You can hear and see the full interview on the Plain Dealer website.
But what does it say about the role of the photographer. Some commentators have pointed out that during the inquiry into the event and even with the pictures of the massacre that survived, many Americans did not believe US soldiers could commit such acts.
Would Haeberle's pictures of the actual killing have changed that, or would they even have been printed? I doubt it, but as David Quigg said on the BBC World Service they would have helped create the context for the pictures we have seen.
Quigg goes on to mention that today we'd press the delete button, and indeed he calls it the "cover-up button".
I think that's possibly a little too simplistic. To follow that through for example you could argue that by simply not taking a picture we are effectively pressing the delete button. A photograph is but a representation of something and the decision to point the camera one way or another will change perceptions of the event depicted. It's also a flat representation and as well as revealing truths some would rather hide, it can also create untruths just as easily.
Haeberle's pictures are without doubt some of the most powerful from the conflict in Vietnam, a conflict that photographically speaking was arguably the high point of photo-journalism. His pictures changed public opinion and there are not many that can make such a claim.
You can read about the events in My Lai in a BBC report marking the 30th anniversary in 1998 and details of the recordings from the army investigation can be read here.
I hope you enjoy looking at the pictures and if you have any comments to make you can do so below.
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