Vermont passed a law in 2014 requiring that grocery food labels will need to declare if the products contain ingredients that were genetically modified. The law is scheduled to go into effect on July 1, even with a pending lawsuit in federal court. As the market in Vermont is relatively small, it is not economically feasible to print labels just for products sold in Vermont, which will effectively make the Vermont labeling law a national standard…
Unless Congress does something by July 1, or other states enter the labeling space and offer their own bills.
As you might guess, the chances of Congress acting by the deadline are relatively slim. An effort to prevent state GMO labeling laws failed in March. There are efforts underway to find a way forward, but with a limited number of legislative days before July 1, there might not be enough time. Given that the Secretary of Agriculture and major food producers are interested in a national standard (if for no other reason than to avoid a patchwork of several different state laws), I think this is another example of the willingness of Congress to not do its job (see the annual tragedy of the budget process for the first, best example of this negligence).
For the record, my personal position on this is much like what the General Mills executive outlined in the blog post I cited earlier. I think GMO food products have been demonstrated as safe for human consumption, but I also think it reasonable to label products with GMO ingredients.