The link between St Valentine's Day and forensic ballistics

Published on 8 February 2019

St Valentine’s Day is the day people are encouraged to show affection but it is also the date of one of the most famous unsolved crimes.

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St Valentine’s Day is the day people are encouraged to show affection but it is also the date of one of the most famous unsolved crimes. 

As part of the gang warfare that formed part of the scene in Chicago in the 1920s and 30s, seven men were lined up against a wall in a Clark Street garage in Chicago and shot on the 14th February 1929. 

The organiser behind the St Valentine’s Day massacre has never been identified, though it would be interesting to know if that would still be the case had this happened today. 

Eye witnesses reported hearing machine guns at the time of the shooting. One man survived the shooting and was taken to hospital but subsequently died, investigators were unable to persuade him to give them any information about what had happened. 

After extensive investigation the police came to the conclusion that two fake police cars had arrived at the garage with their occupants dressed as fake policemen. They entered the garage and on the pretence of arresting the 7 men, lined them up against the wall at 2122 North Clark before shooting them.  Two cars were later found cut up and burnt in an attempt to destroy them. 

Over 70 rounds of ammunition were recovered from the scene itself.  Subsequently, two Thompson submachine guns (Tommy guns) found at a Michigan Bungalow were tested by Col. Calvin Goddard, a pioneer of forensic ballistics who was brought in by wealthy Chicagoans to help solve the crime. 

Col. Calvin Goddard identified the two guns as having been used in the massacre by matching the bullets found at the scene with those from the two Thompson machine guns – this was one of the earliest uses of ballistics evidence in US history. 

Forensic ballistics is the examination of firearms at a scene. As a bullet is loaded into, and fired from a gun marks are left on the bullet or cartridge case.  The marks left on the bullets that had been recovered from the scene of the Valentine’s massacre were compared to those left on bullets fired under controlled conditions from the guns that were later recovered. This type of forensic science is known as pattern recognition, an area of real interest to us at LRCFS.

As a result of this case, Franklin D Roosevelt passed the National Firearms Act of 1934 which was designed to keep the Tommy gun out of the hands of private citizens.

It was widely believed at the time that Al Capone was behind the massacre but evidence came to light 81 years later that may mean that this was an error.  A letter found in the FBI archives suggests that William White, known as 3-fingered Jack had led the attack, motivated by revenge for the death of his cousin.

The garage was demolished in 1967 but for those interested in true crime, it is still possible to see bricks from the north wall of the garage in the Mob Museum in Las Vegas. 

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Story category Research