A criminal defense attorney asked me to look into a homicide a few months ago that involved an air rifle as the murder weapon.
The state contended that the defendant shot the victim in an apartment, put their body into a car, and torched it. Then hid/disposed of the air rifle.
The defense theory of the case was that another individual had performed the murder, and then returned the murder weapon to Wal-Mart, claiming the air rifle wasn’t operational.
The return of the air rifle was caught on security footage, and it occurred roughly two hours after the defense believed the homicide took place.
The air rifle was seized by police, but never sent to the state crime lab for analysis, nor were the autopsy projectiles (pellets).
The autopsy projectiles were of a very interesting design:
Of note was the impressed rifling on the pellet. Specifically there were 12 lands and grooves, with a right hand twist.
When the returned “defective” air rifle was looked at, it was also found to have 12 lands and grooves, with a right twist, AND it also functioned just fine.
Due to a variety of factors, the autopsy pellets themselves could not conclusively be “matched” to the “defective” air rifle, but they couldn’t be excluded either. And there were good sound reasons why they couldn’t be matched.
When loaded with the same type of pellets as the autopsy pellets, the “defective” air rifle would shoot the pellets into a ballistic media block with a penetration depth consistent with what was observed in the autopsy.
These factors, and other as well including no blood found at the suspected murder scene, lead the jury to find the defendant not guilty.
Further investigation also made the person returning the “defective” air rifle a new prime suspect!