It may be laborious, but the only way to disprove this is to list the 50 states (I assumed this is limited in scope to the USA.) and show that in none of them is it true.
Help me out. Pick one, research and edit.
Of course, during this exercise, we may find that there is a place where it IS true. Either way, question answered.
States marked with a * are full participants in NICS, and require FBI approval for purchases. The official form Firearms Transaction Record Part I Over-the-Counter requires a "valid government-issued photo identification" (such as driver's licences) with the current address OR a "valid government-issued photo identification" with a second piece of identification showing the current address. The relevant sections of the form are 20a and 20b. If cheques require more than that in any of those states, we have a winner.
- Alabama *
- Alaska *
- Arizona *
- Arkansas *
- California - No. Can only demand one id for check - via @DVK
- Colorado
- Connecticut
- Delaware *
- Florida
- Georgia *
- Hawaii
- Idaho - May fit the criteria. Need to find a merchant that sells firearms and requires two ID's to pay by check.
- "There is no state permit required for the purchase of any rifle, shotgun, or handgun." idaho.gov The number of ID required to purchase a gun is dependent on other sources' requirements (e.g. ATF).
- The issue of paying by check seems left entirely to the merchant accepting the check as payment. Idaho law seems to not address the issue. Laws regarding merchant acceptance of checks revolve only around what information is stored, not shows of ID.
- Illinois - Requires a Firearm Owner's ID to purchase a firearm, and application for this apparently only requires a single ID (driver's license OR state-issued ID)
- Indiana *
- Iowa
- Kansas * - Appears to have no specific requirements for ID for gun purchase. The only restriction is against selling guns to minors, so presumably a gun store clerk may check an ID to verify age, but there is no requirement to check 2 IDs.
- Kentucky *
- Louisiana *
- Maine *
- Maryland *
- Massachusetts - No. Can only demand one id for check
- Michigan - This might fit the criteria of the claim; additional research necessary
- Requires at most a single state-issued ID to obtain a firearm license (p. 9 of PDF--28.422(3)(c)), and a firearm license isn't even necessary for certain types of firearms.
- It is unclear whether a gun store clerk may request the firearm license in addition to another form of ID at time of purchase.
- Seems to have no law limiting the number of IDs used for check acceptance, only which information can be recorded from the IDs.
- Minnesota *
- Mississippi *
- Missouri *
- Montana *
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico *
- New York *
- North Carolina
- North Dakota *
- Ohio *
- Oklahoma *
- Oregon
- Pennsylvania - Only one form of ID is required to purchase a handgun. For "long guns" (rifles, shotguns, etc.) sold in a private transaction, neither ID nor a license is required. It is still unclear whether the seller can require two forms of ID for a check. Via @ESultanik
- Rhode Island *
- South Carolina *
- South Dakota *
- Tennessee
- Texas *
- Utah
- Vermont *
- Virginia - No. Two IDs required for gun
- Washington
- West Virginia *
- Wisconsin
- Wyoming *
- Washington DC *