A subtle design feature of the AR-15 rifle has raised a technical legal question that is derailing cases against people who are charged with illegally buying and selling the gun's parts or building the weapon.
At issue is whether a key piece of one of America's most popular firearms meets the definition of a gun that prosecutors have long relied on.
For decades, the federal government has treated a mechanism called the lower receiver as the essential piece of the semiautomatic rifle, which has been used in some of the nation's deadliest mass shootings. Prosecutors regularly bring charges based on that specific part.
But some defense attorneys have recently argued that the part alone does not meet the definition in the law. Federal law enforcement officials, who have long been concerned about the discrepancy, are increasingly worried that it could hinder some criminal prosecutions and undermine firearms regulations nationwide.
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Federal regulations define a firearm's “frame" or "receiver” as the piece considered to be the gun itself. But in an AR-15, the receiver is split into upper and lower parts — and some of the components listed in the definition are contained in the upper half. That has led judges to rule that a lower receiver alone cannot be considered a gun.
Design of AR-15 Could Derail Charges Tied to Popular Rifle
1https://www.nytimes.com/aponline/2020/0 ... ethru.html