> <SNIP getting away with shipping a firearm.>

"It must be done boldy. Or not at all." (A Lois Bujold quote from somewhere in The Vor Game.)

I think you did the right thing, though phrasing may have been better. Hindsight is 20/20, etc. In the here and now, I'd probably approach the LEO and offer to let them witness. That'd depend on your local PD, though; I'm lucky in that mine's usually reasonable.