The 1906 Pure Food and Drug Act was a seminal moment in American law. It was a tremendous assertion of governmental responsibility over public health, the result of a wave of concern about the safety of food and medicine. The immediate impetus, as noted in an earlier article, was the muckraking book The Jungle, by Upton Sinclair, which revealed the grotesque and entirely unsanitary world of meatpacking to a shocked public. More broadly, the law was brought about by industrialization, the rise of a middle class, and a shift from the laissez-faire economic perspective of the late 19th century to the interventionist Progressivism of the early 20th. Altogether, the time was ripe for new rules about food, drugs, and that notable combination of the two, alcohol.
At the time the Act passed, a debate about what constituted “Pure” had already been raging in the whiskey world for 50 years. On the one side were the traditional distillers, aging their bourbon and rye for years in warehouses and charging a premium price for the trouble. On the other side were the rectifiers, who took neutral spirits, added colorings and flavorings (often of questionable safety) and sold it as whiskey. The Pure Food and Drug Act gave this longstanding argument a new urgency by introducing labeling standards that everyone was supposed to follow, but that were vague enough to leave this “what really is whiskey” question up to interpretation. Section 8 of the Act said that a label would not be considered “misleading” if it plainly stated that the product was an “imitation,” a “compound,” or a “blend,” as appropriate. A “blend,” it went on to say, was a mixture of like ingredients only.
For the rectifiers, this word choice was a big deal. People would buy a blend, but they might not buy a compound, and they definitely wouldn’t buy an imitation. They set to work lobbying the Secretary of Agriculture, but were rebuffed: The Secretary found that colorings and flavorings simply could not be considered like ingredients.
The economics of the question were too great, however, for the buck to stop there. In addition to the domestic rectifiers, international trade was at stake: Canadian whiskey and Scotch non-single malt whisky are made in a similar style and were at risk of having their own sales depleted. At the same time, there were concerns that if rectified “whiskey” could be labeled as such, lab-designed versions of any product could could claim similar authenticity on their labels. The lobbying intensified, with the rectifiers eventually convincing the Secretary to change his mind and support them, leading his chief chemist to go behind his back and stage a rectifying demonstration for the President himself, Theodore Roosevelt. Roosevelt set his Attorney General to the task of determining a suitable definition, and the AG came down firmly against the rectifiers. Roosevelt supported him, and when the courts held up the decision, it seemed like the matter might be settled.
Political pressure remained strong, however, with Congressmen and Senators from rectifying districts pushing for change. William Howard Taft, who had seemed to lean towards the rectifiers during Cabinet discussions when he was Secretary of War, succeeded Roosevelt in the White House in March 1909, and was quickly set upon by the dueling sides. Taft agreed to reconsider the issue, and delegated the task to his lawyer, the Solicitor General, whose eventual decision pleased exactly no one. Both sides appealed to Taft to render his own, final verdict, and he agreed.
Taft, you may know, is the only person to serve as both President and, later on, as Chief Justice of the Supreme Court. The man loved a good legal question, and he dove deep into this one. He took months to think it over (I mean, I’m sure he was doing other things, too, but still) and finally issued what became known as the “Taft Decision” on December 26th, 1909. In it, he declared that any spirit made from grain could be called whiskey. Time in a barrel is not what gives it its name, and the addition of flavoring and coloring do not take the name away from it. To salve the burns of the straight whiskey proponents, he ordered that every bottle labeled as whiskey also include a description with more details (as in, “whiskey made from neutral spirits). Case closed.
The heart of a good code of laws is the definitions section. If the meaning of words is unstated or unclear, the door is open to confusion and conflict. The quest to define whiskey raised important questions for the liquor trade and beyond, as a newly industrial and regulation-happy America tried to decide what was okay to do with our newfound chemical know-how. It also brought to light just how little the average consumer knew about what they were drinking or eating, and how much everyone relied on labels and brands. We may think of ourselves as better-educated consumers now, with our behind-the-scenes tours and well-traveled palates, but for most of us, when we walk into the liquor store or any store, we’re relying on the same cues as every generation before us. 
 The main source for this article is a 1910 recounting of the events leading to the Taft Decision: Mills, H Parker. “What Whiskey Is.” McClure’s Magazine (1893-1926); Apr 1910; VOL. XXXIV, No. 6; ProQuest pg. 687. I also referenced the Pure Food and Drug Act, a newspaper article from the time period (Lewiston Daily Sun. “Taft Defines Whiskey.” December 27, 1909, pg. 1. Accessed through Google Archives.), and a second magazine article: Outlook Magazine. “What Is Whiskey?” January 8, 1910; 94, 2; ProQuest pg. 47