Updated

As the $15-an-hour minimum wage movement continues across the country, critics question whether the push is truly a grassroots effort.

The Freedom Foundation, a free-market think tank based in Washington state, claims a union-backed organization called Working Washington paid at least one Subway worker $75 to protest the fast-food wage earlier this year. Working Washington is pushing for $15-an-hour minimum wage and held three protests at fast food restaurants in Seattle this summer.

A copy of a check to a worker from Working Washington comes from the lawyer representing Subway in a case in which an employee was fired after the protests, according to the Freedom Foundation report. It's unclear how many workers might have been paid to protest, but Freedom Foundation officials argue it shows these movements are more the work of union organizing.

"Protests over the minimum wage have been popping up all over the country this year. Not only are labor unions supporting these protests, in many cases they are fabricating them," Freedom Foundation labor policy analyst Max Nelson told Northwest Watchdog. "Our finding that the SEIU was paying fast food protesters in Washington earlier this year just goes to show that these protests are part of a sophisticated PR campaign, not a grassroots uprising."

Northwest Watchdog left a message with the media contact for Working Washington and will update when we hear back.

The report also finds that the national Service Employees International Union  funneled a total of $3,652,340 in monthly payments through SEIU Leadership Council 14 to Working Washington from 2011-2012. Working Washington has also been a big part of the SeaTac $15-an-hour minimum wage initiative that went to voters earlier this month and is expected to win what has been a close race when official results are released later Tuesday.

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