Professor alexandre lacassagne a pioneer in bloodstain analysis

Alexandre Lacassagne (1844-1921) was a professor at the University of Lyons, France. He was the first scientist to study bullet markings and their relationship to specific weapons. In 1889 in France, Professor Lacassagne removed a bullet from a corpse. He noted that the rifling impressions on the bullet were from a weapon with seven lands and seven grooves. A number of possible suspects were rounded up and their weapons turned over to Professor Lacassagne for examination. Ultimately, the professor determined that only one of the submitted weapons had seven lands and seven grooves. On that basis the gun's owner was convicted of murder.

This finding was significant in that it was the first time that rifling marks on fired bullets had been used to exclude certain weapons. Thus, the foundation for modern firearms identification, as applied to projectiles, had been laid.

Are there any potential flaws in the basis on which the gun's owner was convicted? As noted in the discussion on firearm types, the number of lands and grooves in a gun barrel does vary; however, two other questions should have been considered in Lacassagne's examination: How many other guns with seven lands and seven grooves exist, and how many could have been used to fire the fatal shot? Another concern would be the fact that the direction of twist of the rifling could either be to the left or the right. Thus, if numbers of lands and grooves alone were considered, a serious error could have been involved in the conviction.

In 1898 in Berlin, chemist Paul Jeserich was provided with a bullet from a murder victim along with the suspect's revolver. He was asked to see if he could determine whether the revolver was used to fire the fatal bullet. Jeserich unknowingly stood at the brink of historical prominence as he proceeded to test-fire the revolver, prepare photomicrographs of the surfaces of both test and evidence bullets, and compare the microscopic markings on the bullet surfaces to each other.

As fate would have it, Jeserich did no follow-up work and made no further effort to develop his methodology. Thus, his place in firearms identification history is analogous to a modern-day musician who goes no further than getting one song on the record charts and subsequently becomes known as a "one hit wonder." Nonetheless, Jeserich brought firearms identification closer to its modern-day counterpart by recognizing the importance of individual characteristics (accidental, random characteristics) as the appropriate means for establishing identification of bullets to specific firearms.

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