The OP was referring to the federal government in the first post. My comments were in regards to that. Prop 37 was not even mentioned in the first post to this discussion nor was the first post focused on the role of States in GMO labeling.
I see no problem at all with States mandating labeling as long as it is authorized under their State constitutions.
The voluntary labeling approach would work, though, since there is a growing demand in the marketplace for non-GMO foods. I would not expect Monsanto to voluntarily label anything, but others would and they would reap the benefits of doing so.
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