What is the law on NICS checks when purchasing firearms?

Question

In the US it is common practice for sellers of firearms to follow the following process:

1. Ask buyer to fill out ATF form 4473
2. Call NICS to verify that the DOJ/FBI is not aware of any prohibitions against the transfer (I'm not sure which agency exactly handles this call)
3. NICS may approve or deny the transfer right away, but they may also delay it so they can take additional time (days) to review the request

There is a commonly stated provision that if NICS does not make a decision in 3 days, the seller may proceed with the transfer. So in effect transfers are automatically approved after 3 days.

I know there are various laws prohibiting the transfer of firearms to certain people, such as felons or fugitives. However, is there a law on how a transferee is to determine that a buyer is not such a prohibited person, and how long this may take? Specifically, I'm curious to know:

• Is there a law that background checks may not delay a firearm transfer by X days?
• Is there a law saying that background checks may not delay a firearm transfer "excessively" without giving a number of days?
• Is the above process with 4473, NICS and the 3 day cap specified in a law, or is it just a policy the ATF came up with on its own?
• If the DOJ/FBI uses a way to delay the transfer by more than 3 days, are they breaking any laws?

Clearly, when the above process was put in place, there was some concern that the background check would be a way for the government to slow walk each purchase and infringe on the rights of the public to keep and bear arms. Accordingly, there is a rule that the background check will take at most 3 days, and if it's not done by then the transfer is approved by default. This seems a reasonable compromise between the need for an opportunity to catch prohibited transferees, while also limiting the harm to those that are not prohibited.

To summarize the question, where is this 3 day compromise coming from? Did Congress pass a law to this effect, or did SCOTUS (or another court) rule that it must be so? Or is this something the ATF decided to do on their own, without having to?

Answer 1

Where is this 3 day compromise coming from?

The three (business) day requirement is statutory, and can be found in 18 U.S. Code § 922:

(A) before the completion of the transfer, the licensee contacts the national instant criminal background check system established under section 103 of that Act;

(B)

(i) the system provides the licensee with a unique identification number; or

(ii) subject to subparagraph (C), 3 business days (meaning a day on which State offices are open) have elapsed since the licensee contacted the system, and the system has not notified the licensee that the receipt of a firearm by such other person would violate subsection (g) or (n) of this section, or State, local, or Tribal law; and

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