Photo claimed to include Wyatt Earp, Butch Cassidy, the Sundance Kid, Teddy Roosevelt and Judge Roy Bean, among others
By Kevin Connolly
BBC News, Washington
The glamour of notoriety that colours our perceptions of criminals is as strong now as in the days of the "Wild West".
If it is real, it is extraordinary: a moment when the myths and legends of the Old West crystallised for a moment into a single group photograph before evaporating again into the anonymity of the hot afternoon.
The 15 men in the picture are arranged along the wooden veranda of a hotel in the resort of Hunter's Hot Springs in the summer of 1883.
In the fashion of the time, no concessions are made to the brutal heat. Waistcoats are worn, ties are neatly knotted, bowler hats are sported.
They are relaxed but formal.
One of the seated figures leans back confidently against the upper step behind him. Another looks slightly priggish with his legs crossed at the knees and his hands settled in his lap.
They look tough. Like men who meet a lot of tough guys and generally find that they are tougher still.
Which is not surprising when you consider that this was a gathering of some of the most powerful and desperate figures from the old West in the dying days of its wildness.
If it is real.
White House hopeful
The story is told that the 15 men include Butch Cassidy and the Sundance Kid, Wyatt Earp, his brother Virgil and their friends Doc Holliday and Bat Masterson.
Theodore Roosevelt was US president from 1901 to 1908
The lounging figure is - or might be - Judge Roy Bean, who conducted trials in the bar of the saloon he owned in Texas and encouraged jurors to buy drinks between cases.
A few feet away, apparently on an upturned crate, sits a figure identified as Theodore Roosevelt, the future president.
You would not, of course, find a modern hopeful for the White House posing nonchalantly with bank-robbing ne'er-do-wells, but these were different times.
We know the picture is genuine in the sense that it is a real photograph of 15 men from the 1880s. We just cannot be quite sure who they were.
We know it could be real, which is what makes it so fascinating.
Teddy Roosevelt did retreat into the western wilderness in 1883 after the death of his first wife and when Butch Cassidy, Wyatt Earp, Doc Holliday and Bat Masterson were all dotted somewhere around America's ragged and dangerous western frontier.
The story goes that the men were brought together to celebrate the opening of new railroad track - a big event at a time when the steel arteries of the railways were carrying the boundless wealth of a booming America westward, hotly pursued by posses of hookers, crooks and lawmen.
There is nothing implausible about the good guys and the bad guys hanging out together or posing for a photograph, by the way.
Butch Cassidy and the Sundance Kid was the top-grossing film of 1969
The lines between those who enforced the law and those who broke it were a little more fluid back then.
When Butch Cassidy robbed his first shop, for example, he left an IOU on the counter for the things he stole.
Wyatt Earp, the celebrated lawman, was also a gold prospector, buffalo hunter and boxing promoter. And he almost certainly helped to run a brothel at one point too.
Nor is there anything odd in the idea that the men were celebrities.
Masterson and Earp were both famous while they were still alive and the subjects of admiring and highly coloured accounts of their exploits.
Earp even ended up moving to Hollywood and mixing with the very actors who played him.
Butch Cassidy and his accomplices once posed for a portrait in Fort Worth, Texas, at the height of their notoriety, something you might want to consider avoiding if you ever find yourself on the run, accused of murder and bank robbery.
Oddest of all, of course, is the very fact that we know who these men were.
I bet not one of us in 10,000 remembers who was treasury secretary in 1883 but, whoever it was, he would have filled miles of newspaper columns at the time. And he would be stunned to discover that these dusty reprobates remain household names while he is long forgotten.
Could present-day convict John McCluskey be a legend some day?
In part, of course, that is about the ability of Hollywood to condition our sense of the past.
A history written in blazing shades of light is always going to seem more vivid than the dusty accuracy of the library book or the dodgy scholarship of the internet.
In part though, it is about America's curious habit of romanticising violent crime.
John Dillinger, Bonnie and Clyde, Baby Face Kelly and Al Capone are all lastingly famous too, while the statesmen and even the sports stars who were their contemporaries are long-forgotten.
Sometimes we soften the edges of their brutal stories with spurious touches of glamour or philanthropy but mainly, I think, they are remembered because they appeal to some darkly anarchic, anti-establishment streak in the American soul.
On the day I found that photograph hanging in a bar in Cheyenne, Wyoming, America's law enforcement agencies were looking for an escaped convict called John McCluskey, and his cousin and lover Casslyn Lynch, who helped him break out of prison.
Their squalid, violent odyssey across the country awoke curious echoes of the past.
The media were at it, of course, calling the couple a new Bonnie and Clyde but the story had law officers too reaching for the antiquated patter of the gangster movie and the gumshoe novel.
The criminals were "on the lam" we were told and they "wouldn't go down easy".
But we were not to worry because the "Feds" would be "all over them like a cheap suit".
How odd it is that there is a chance, however small, that one day those two might be remembered when we have forgotten the name of whoever is currently treasury secretary all over again.
And perhaps there is even a chance that one day - in some windy, dusty town out on the prairies - a visitor will find a photograph of them and wonder if it is real.
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