Changes to the forms required for firearms purchases asking questions about the buyer’s race and ethnicity have drawn strong reaction from gun dealers, privacy advocates and lawmakers.

Form 4473, required for an over-the-counter sale by a federally-licensed dealer, now asks first whether a buyer is Hispanic or Non-Hispanic, followed by a question delving into more detailed race-based information.

Critics want to know why the Bureau of Alcohol, Tobacco, Firearms and Explosives quietly made the change in 2012.

Sen Roy Blunt, R-Mo., sent a letter to ATF Director Todd Jones asking why the information was being collected and whether the data had ever been used to restrict someone's ability to purchase a firearm.

"What does that possibly have to do with whether you would pass the background check for a firearm or not?" Blunt asked.

In a response to Blunt, the ATF said Wednesday it has been collecting some type of race information on Form 4473 since 1968, but that it has never compiled or maintained it in any database.

Among its reasons for obtaining the ethnicity and race data, ATF said, was for "purposes of identification in conjunction with the required background checks." The agency also stated that the Office of Management and Budget "required ATF to make changes to the format of the questions during the standard Paperwork Reduction Act approval process" in 2012.

In the past, the OMB has explained the need for the race and ethnicity data as a way to help the federal government enforce civil rights laws by monitoring "equal access in housing, education, employment and other areas."

Privacy advocates, including the American Civil Liberties Union, are skeptical of the ATF's explanation suggesting that the OMB left it no choice. ACLU Legislative Affairs Director Laura Murphy told the Washington Times, "There is nothing [in ATF or OMB's website links addressing the change in policy] that supports the requirement that ATF collect race-based information. The OMB guidance merely describes what categories of race should look like if information is collected."

Calling the questions "highly intrusive" and "unnecessary," Rep. Diane Black, R-Tenn., has introduced a House bill that would ban the ATF from collecting the data.She also cited a concern many gun dealers have voiced, claiming that the multiple race and ethnicity questions are confusing to some buyers.

If the forms are filled out incorrectly, dealers can potentially face stiff penalties.