The earliest firearms identification case occurred in 1835 in the City of London. Gun crimes have increased immeasurably since then, but so too has the criminalists understanding of ballistics.

Once a gun has been fired there are all manner of avenues investigators can pursue to bring about an arrest. The bullet casings and bullets themselves reveal telltale signs under the microscope. Experts look for the ‘rifling’ marks to distinguish which gun was used to propel the bullet. It’s also possible to trace the bullet’s trajectory by aligning bullet holes and entry points to determine the exact spot the bullet was fired from.