Two Berkeley residents who oppose a proposed tax on sugar-sweetened beverages filed a petition against the city Wednesday, alleging bias in the ballot language for the tax.

Last month, Berkeley City Council voted unanimously to place an ordinance imposing a 1-cent-per-ounce tax on sugary drinks on the November ballot. The petition alleges that with the ballot label it plans to use, the City Council “illegally injected politically-charged language tracking its partisan political views in favor of the tax measure into the voting booth.”

San Francisco officials also voted to put a soda tax on the ballot this November. If the measures pass, San Francisco and Berkeley will be the first cities in the country to implement such a tax.

Leon Cain, one of the petitioners, works as an associate for Rodriguez Strategies, a Los Angeles-based public affairs firm. The CEO of Rodriguez Strategies leads “coalition building efforts” in California for the American Beverage Association, according to its website.

The ordinance’s ballot label uses the phrase “high-calorie, sugary drink,” which the petition says is misleading.

“The tax applies to drinks that no reasonable person would regard as ‘high calorie,’ ” the petition says.

Although the measure is crafted around the claim that it will combat obesity, it actually applies to a number of drinks that do not contribute to obesity, the petition alleges.

According to the ballot label, the tax would apply to drinks such as soda, energy drinks and presweetened tea but would exempt baby formula, medical drinks, milk products, 100 percent juice and alcohol.

The petition also takes issue with the analysis accompanying the ballot label, which says the ordinance would apply to “low-nutrition products.” According to the petition, the tax would apply to juice drinks that contain 100 percent of the recommended daily dose of vitamin C, as well as reduced-calorie sports drinks that provide “hydration, electrolyte replacement and other benefits to athletes.”

Additionally, it alleges that the analysis, which states that the tax would be payable “by the distributor, not the customer,” misleads voters by implying that consumers will not bear any extra cost. The ordinance aims to discourage the distribution and consumption of sugary drinks by raising their prices, thus passing on the burden to customers eventually, the petition alleges.

The petition, which was first tweeted by Berkeleyside, is for a writ of mandate, asking a judge to prohibit the use of the allegedly biased ballot label and analysis.