Let's run through this just to be clear.That's not true. The law says it's legal "as long as he or she does not know or have reasonable cause to believe the person is prohibited from receiving or possessing firearms under Federal law." It doesn't place an affirmative duty to know, or to find out. If I don't have actual knowledge that you're prohibited, or have reason to believe it, I'm good to go in the law's eyes.
You're selling a gun, maybe even listed here.
You get a buyer who you have no knowledge of.
You meet in a parking lot where he tells you his name is John Smith and he's OK, not a felon.
You sell him the gun.
Six months later he's caught committing a crime with the gun in his possession, and Oh he does have a record.
In exchange for a lesser sentence he gives you up as the source of the gun.
Now the law clearly puts the burden on the seller.
" 159:7 Sales to Felons. – No person shall sell, deliver, or otherwise transfer a pistol, revolver or any other firearm, to a person who has been convicted, in any jurisdiction, of a felony. Whoever violates the provisions of this section shall be guilty of a class B felony."
And the exception to this:
" 159:14 Exemption. – None of the provisions of this chapter shall prohibit an individual not licensed under the provisions thereof who is not engaged in the business of selling pistols or revolvers from selling a pistol or revolver to a person licensed under this chapter or to a person personally known to him."
159:7 has nothing about knowledge of the buyers status or the intent of the seller. Only the fact that it occured.
159:14 offers the exception to this by allowing the buyer to be personally known to the seller as sufficient evidence that the seller had reasonable proof that the buyer wasn't prohibited. This is an exception or defence to 159:7
I don't have the reference, but I do know it's been established that the buyer having a P&R is also considered sufficient evidence that the buyer is not prohibited.
Now if you want to stand up in court and testify that you personally knew the convicted felon and believed he was not prohibited, and you only just met him, well go for it and enjoy your stay.
Keep in mind that the very person you are claiming to "personally" know is also testifying that he only just met you, and has no idea who the F you are.
Fortunately I don't even have to win this argument, if I inadvertently sell to a felon, well I've got the P&R to backup my position so I'm not even going to spend a day in court.
On the other hand, if it happens to you without the proof, you will spend many days in court, racking up all those legal fees, and you'll probably get convicted. But even if you aren't convicted, you'll be out the 10-20K in legal fees.
Good luck.