"That's the proof you should actually be asking for," Boxer told CNN.
The plaintiffs' attorneys believe a bottle of Budweiser has 4.7% alcohol instead of the label's 5% figure. Over a year of brewing, that alcohol difference amounts to "tens of millions" of dollars in savings for the company, Boxer said.
"The most accurate data, as we discussed, is going to come from Anheuser-Busch because they do their testing six times per second," Boxer said. "And they use different technology, in fact, from the laboratories you used."
Earlier this week, two California residents sued Anheuser-Busch, alleging the company waters down Budweiser and other beers "significantly" to boost profits.
The class-action lawsuit alleges that the maker of the "King of Beers" has the technology to precisely control the amount of alcohol in its beers but adds water so the alcohol is well below the advertised figure of 5% by volume, the suit said.
"There are no impediments -- economic, practical or legal -- to AB accurately labeling its products to reflect their true alcohol content," the 18-page lawsuit said. "Nevertheless, AB uniformly misrepresents and overstates that content."
The beer maker has rejected the lawsuit's allegations and now points to media outlets' independent tests to bolster its response.
"The claims against Anheuser-Busch are completely false, and these lawsuits are groundless," Kraemer said earlier this week. "Our beers are in full compliance with all alcohol labeling laws.
"We proudly adhere to the highest standards in brewing our beers, which have made them the best-selling in the U.S. and the world," he said.
The brands that the suit alleges are watered down are those tested by CNN and Bud Lite Platinum, Michelob, Michelob Ultra, Hurricane High Gravity Lager, King Cobra, Busch Ice and Natural Ice.