Last week the battle over labelling genetically modified foods took a bizarre turn in the United States as a number of trade groups representing big food multinationals filed a lawsuit against the state of Vermont.

Groups led by the Grocery Manufacturers Association, which represents the world's most powerful food brands, filed a complaint in federal district court in Vermont on Friday 13th, challenging the state's recently introduced labelling law, which would require labelling of foods containing genetically modified organisms (GMOs). 

Vermont's labelling law, passed in May, is the first "no strings-attached" legislation to require mandatory labelling of GM food ingredients in the United States. Although such laws exist in the EU, China, Australia and Japan, consumers' groups that believe they have a "right to know" what they are buying and consuming have faced fierce opposition to introduce such measures in the US.

The current struggle to introduce labelling began in 2012, with California's Proposition 37. There, the proposed labelling legislation was narrowly defeated, but it cost food manufacturers' groups a cool $46 million (£28m) to chip away at the overwhelming support Prop 37 initially enjoyed; GMA donated $2m to the 'no' campaign in California.  The pro-labelling camp only managed to raise a fifth of the funds available to their adversaries.   

Since that time, Maine and Connecticut have introduced conditional labelling laws that will only come into effect if there is sufficient support from other states, and proposed labelling measures were also narrowly defeated in Washington.

Filing its complaint, the GMA claimed Vermont's new law is "unconstitutional" and, in a statement released on Friday, described the new legislation as "a costly and misguided measure that will set the nation on a path toward a 50-state patchwork of GMO labelling policies that do nothing to advance the health and safety of consumers," adding, "Vermont has effectively conceded this law has no basis in health, safety, or science." 

The big food group also claimed Vermont legislators had acted "as a pass-through for the fads and controversies of the day" in passing the new law.

The US Organic Consumers Association responded that it would contribute to help defend the fledgling labelling law. The organic group said in its own statement, "These battles that pit consumer health and rights against multi-billion corporations belong to all of us" and called on supporters to donate to defend their 'right to know'.

The Association warned that, "If… the GMA succeed in overturning Vermont’s GMO labeling law, lawmakers in the other 29 states that are currently considering GMO labeling bills will drop them like hot potatoes."

Ahead of a demonstration against the GMA's actions on Monday 16th, consumer protection advocate Falko Schilling said, "This is a direct assault on Vermonters' right to know what is in their food. This news is upsetting but not unexpected, and as we speak the State and members of the Vermont Right to Know GMOs coalition are working to mount a strong defense of the law." Schilling called on supporters of the new law to "Show the GMA we aren't afraid of their strong arm tactics."

Last week, US Department of Agriculture Secretary Tom Vilsack sparked controversy when he took aim at a number of 'red line' food safety issues EU negotiators had said would not be up for negotiation, as the ongoing Transatlantic Trade deal (TTIP) talks moved round to agriculture. Vilsack was critical of the EU's precautionary approach which proscribes certain GM crops and hormone treated beef from entering the bloc, to the detriment of powerful US exporters' organisations.