From the seven corpses that contrasted like gloomy shadows against the white wall of a Chicago auto repair shop, thick rivulets of blood gushed out and slowly drained into a drain.
A group of neighbors had gathered at the entrance of the establishment, attracted by the noise of the shots that had taken them out of their daily lives. that Valentine's morning in 1929.
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They wanted to see for themselves a common image of Chicago in the late 1920s, a city corrupted by the mafia after nine years of that failed social experiment that was the prohibition of alcohol consumption (the infamous dry law), which had caused numerous vendettas between gangs.
But this massacre, carried out on February 14, 1929, was far from being another confrontation. His brutality marked a milestone in escalating gang violence that had promoted prohibition in the US, and is seen by many historians as the event that precipitated the beginning of the end of alcohol prohibition.
Furthermore, almost 100 years after it occurred, it remains unclear. Is one of the "cold cases" (cold cases) most emblematic of the country.
And it is also believed to have precipitated the downfall of Al Capone, the "boss of bosses" of Chicago organized crime in the 1920s, despite the fact that there was never any concrete evidence linking him to the killings or a conviction against him.
But how did a massacre that occurred almost 2,000 km away from where Capone - who had supposedly traveled to Florida to attend to health problems - led to his downfall?
a godfather of crime
By 1929, Al Capone was already the most recognized name in the world of US crime.
Alphonse Gabriel Capone, or "Scarface", as he was known in the world of crime, spent the first half of the 1920s climbing to the top of the Colossimo family. In 1925, after a failed assassination attempt forced the head of the family -"big jim" Colossimo- to retire, Capone became the kingpin of the organization.
"The last three years (before the massacre), Capone had been the most famous gangster in the US," biographer Jonathan Eig tells BBC Mundo, who in his 2010 account of the mobster's life presented a new theory of facts behind the St. Valentine's massacre.
"Part of it's because he wasn't trying to hide: he liked being a celebrity. Actually, he was the first famous gangster in the US. He was someone who gave interviews and posed for photos."
This despite the "empire of crime" under his control: "gambling, prostitution, illegal liquor sales, bribery, narcotics, robbery, 'protection deals,' and murder" in 1929 Chicago were of Capone, according to an FBI report.
To achieve impunity, he kept the investigations of his crimes within the local jurisdiction of Chicago, where he used corruption to make them disappear.
This strategy worked well for him until February 1929.
The Valentine's Massacre
According to the forensic reconstruction carried out by the authorities the day after the San Valentin massacre -based on the information collected at the scene and the testimonies of eyewitnesses-, on the morning of February 14, a group of four and five men - at least three of them dressed as policemen - got out of a big black Cadillac in front of the garage.
Inside the workshop was a group of seven men: six of them impeccably dressed in suits and ties - one of them had a gardenia in his lapel - and the mechanic, who was wearing his overalls. They were all members or close associates of the criminal organization of the Morán brothers, which supplied liquor to the north side of Chicago. Also, the mechanic's dog was tied to one of the cars.
The moment they were seen coming in, the men in the workshop put up no resistance despite being heavily armed. In addition, it is surprising that among the victims were Frank and Peter Gusenberg, two well-known criminals who were a headache for the city authorities.
The men dressed as police officers asked the gang members to move away from windows and doors and then fired their machine guns, leaving behind a pile of bodies riddled with holes and lead. In the end, only the bitter howls of one of the two witnesses who were still alive, the mechanic's dog, could be heard.
A few seconds before dying of his injuries, the only human survivor of the attack, Frank Gusenberg, managed to whisper: "It was the cops"(it was the policemen) .
"It was much more violent than most of the killings between criminal organizations in the 1920s," says Eig.
"In addition, it was photographed and published on the front page of newspapers, and tabloids in particular, were publishing photographs that would not have been published a few years earlier," he adds.
This would put all the attention on the most famous capo in the city.
The Boss Capture
After the massacre, and in the face of the violence that Prohibition had provoked, newly elected President Herbert Hoover made the fight against organized crime one of his top priorities.
On March 20, he invited a group of prominent Chicago residents to the White House and said: "They told me that Chicago was in the hands of gangsters. That the police and magistrates were under their control. That the governor of the state was useless and that only through the federal government could the city regain the ability to govern itself."
"Up to that point, crime fighting was really a local, local police department issue, without much federal jurisdiction," says Jonathan Eig.
"But after the Valentine's Day massacre you begin to see J. Edgar Hoover and his (newly created) FBI begin to gain more power and become involved in the fight against crime around the country."
In fact, Capone's arrest had nothing to do with the killing itself.
A series of minor arrests - one for failing to show up to a subpoena, another for concealing weapons - gave the US tax agency enough time to build a tax evasion case against the mobster. He spent six years behind bars, and when he came out of it, his mind had been affected by the insanity caused by syphilis, thus ending his criminal life.
"First of all, (the massacre) led to a conviction for tax evasion because the government just wanted to get him off the streets," says Eig.
"The carnage really upset a lot of people. It made it look like the US was out of control, gangs were running the cities, and Capone became the target."
But also, the killing "helped remind people that prohibition (alcohol) was not working, and I think it helped pave the way for the end of prohibition."
the forgotten tests
While writing his Capone biography, Eig spent time digging into Chicago police and FBI files for details of the massacre.
This is how he managed to find things that were never taken into account in the investigation, and that could give a solid explanation of the facts.
"It's one of the biggest unsolved cases. There's never been anything solid to connect Capone to the case. Just because it was in Chicago, and because there were machine gunners and bootleggers involved."
In his investigation, Eig found a letter dated January 28, 1925, sent by a citizen of the city to Hoover, the FBI director, in which he tells him that he made an "undercover investigation" and found that the killing was related to the death of the son of a police officer.
In other words, according to this theory, the men who shot while dressed as police officers were actually police officers acting out of revenge against the Gusenberg brothers, who would have killed the young man.
Given Capone's prominence in the city's world of crime, and the possible involvement of police officers in the killing, the capo became the ideal scapegoat.
Eig believes that Capone's taste for the spotlight and public attention precipitated his downfall.
“The massacre made the notoriety that he already had explode and the federal government came down on him.” The rest is history.