We’re all accustomed to the idea that alcohols of different strengths will be regulated differently. For the most part we do that by type: beer has these rules, wine has those, and liquor has these, those, theirs, the whole nine. But several states dive in a little deeper, distinguishing between light beer and heavier beer. And they all use the same cut-off line: 3.2% alcohol by weight. In Utah, Oklahoma, Minnesota, Kansas and Colorado, you can buy beer below 3.2% ABW in a grocery store, but nothing higher.
Seems a little arbitrary, doesn’t it? Why 3.2% ABW? And since when do we measure alcohol content by weight, anyway? The answer, like with so much else we talk about on this site, is 1933, the end of Prohibition.
FDR had won the presidency with a promise to repeal the 18th Amendment. While he put that in motion right away, it had to get ratified by 36 states. That, it was thought, could take years, and with the Great Depression in full swing, the government wanted to get the brewing industry back up and running sooner rather than later. Thankfully, the 18th Amendment did not expressly forbid all alcohol, just “intoxicating liquors”. In fact, some people who supported the Amendment apparently did so thinking it would just ban spirits, and leave beer and wine alone. The fuzziness of “intoxicating liquors” opened the door for the government to allow low-alcohol booze before the 21st Amendment actually passed. Congress quickly drew up a bill granting states permission to allow beer and wine up to 3.2% ABW.[i] FDR signed it (famously quipping, “I think this would be a good time for a beer!”) and it went into effect on April 7—now celebrated as National Beer Day.
The 21st Amendment did not take years to pass. It was adopted within nine months, with Utah, of all states, the 36th to ratify it. That was the end of the federal 3.2% law, and most states got rid of their versions as well. But a few have held onto the distinction ever since.
So, that’s why all those states use the same percentage, but why did the authors of the original bill choose 3.2% ABW?
Apparently, it’s just as arbitrary as it seems. Different numbers were thrown around—2.75%, 3.05%, etc.—often with some quasi-scientific claim about where “intoxication” began.[ii] Congress picked one, and nobody challenged it.
[ii] See Swain, Martha. “Pat Harrison: The New Deal Years.” University Press of Mississippi: Jackson, 1978. Pp. 40-41