A recently passed right-to-work law in Missouri was criticized by labor unions Monday during their annual four-day convention in St. Louis.

The AFL-CIO convention brings together union leaders and advocates from across the labor movement. Speakers discussed a range of political and workplace issues including right-to-work. The convention highlighted a campaign out of Missouri which seeks to repeal the statewide right-to-work law.

The We Are Missouri campaign is being led by labor unions and supporters hoping to repeal the law. Members of the campaign took to the stage during the convention to highlight what has been done so far. They were able to get a repeal of the policy on the ballot next year after collecting 310,567 signatures.

Missouri has considered several right-to-work bills over the years before finally passing one Feb. 6. The policy outlaws mandatory union dues or fees as a condition of employment. But supporters of the policy still face resistance from labor unions and other critics. We Are Missouri showcased a video during the convention of workers from the state who oppose the new law.

“We know that right-to-work is wrong for all Missourians,” a retired railroad conductor said in the video. “We are here today united as Missourians, united as workers to tell politicians and special interests we will not be defeated.”

The AFL-CIO is the largest federation of labor unions in the country at 12.5 million members. The convention has covered topics from worker rights, wage inequality, racial inequity, and the current state of politics. AFL-CIO President Richard Trumka was also reelected to another four years at the start of the convention.

Labor unions and their supporters argue that optional dues encourage workers to free-ride. They are obligated to represent all workers regardless of whether they pay dues once they get voted in as the exclusive representative. They have denounced the policy as an underhanded attempt by special interests to destroy unions by attacking their funding.

The free-ride argument is used against both lawsuits challenging mandatory union payments and right-to-work laws. But those in support of the policy argue it’s really about worker choice. Many unionized workers might genuinely dislike their union and the benefits they provide.

Americans for Prosperity (AFP) has conducted a months long campaign to educate people in Missouri about the new law. The group has been an advocate for the policy and hopes to show workers what their new rights are under the law. The six-figure effort has also included digital video and display ads, direct mail, events, door-to-door canvassing, and phone banking. They sent the fourth round of mailers Monday about the new right to work law.

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