In an en banc 13-3 decision, for varied reasons, the Fifth Circuit struck down BATFE's reversed position, which declared “bump stocks” to be machine guns. Here is one of the three reasons BATFE's flagrant over-reach was rejected by the court:

“Finally, we note a third reason why Chevron deference does not apply in these circumstances: that ATF has adopted an interpretive position that is inconsistent with its prior position. To apply Chevron here would contravene one of the rule's central purposes: ‘ promote fair notice to those subject to criminal laws.'

If we were required to defer to the Government's position, the Government could change the scope of criminal liability at any time. Indeed, that is exactly what it has done here. Until 2017, the ATF had never classified non-mechanical bump stocks as machineguns. But now the interpretation is reversed, and the Government would criminalize behavior that it long recognized was lawful. . . .”

Read the decision here:

https://www.ca5.uscourts.gov/opinions/pub/20/20-51016-CV2.pdf?utm_medium=email