GRAND RAPIDS, Mich. – A special education teacher in Grand Rapids, Michigan recently filed an unfair labor practice complaint against her teachers union and district for refusing to let her drop out of the union.

Becky Lapham alleges the Grand Rapids Education Association teachers union, the statewide Michigan Education Association, and Grand Rapids Public Schools violated her rights under the state’s right-to-work law by refusing her request to terminate her affiliation with the GREA, Mlive.com reports.

Lapham filed an unfair labor practice complaint with the Michigan Employment Relations Commission over the issue earlier this month.

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The 11-year teacher, who works at the Lincoln Developmental Center, submitted a letter of resignation to the GREA Jan. 31 and “requested to pay a reduced fee covering only her costs of collective bargaining, contract administration and grievance adjustment,” according to the news site.

She also asked the union to provide an itemized breakdown of her fees and dues, as required by law. The union responded with an email denying her request because it wasn’t submitted during the MEA’s “August window” – the union’s designated time for opting out, Mlive reports. The union also threatened to refer her to a collection agency if she doesn’t pay her full dues.

GRPS and GREA ratified their most recent teachers contract in March 2013, and in August of 2013 amended the agreement to explicitly state employees who don’t pay dues will be fired.

The National Right to Work Legal Defense Foundation, which is representing Lapham in the case, “argues that contracts or amendments made after the (right to work) law went into effect on March 28, 2013 must respect workers’ right to refrain from paying dues.”

Lapham is the only the latest public school employee to take issue with how the MEA and its affiliates are handling an influx of requests to opt out of their unions since right-to-work became state law.

Two other teachers – Coopersville kindergarten teacher Miriam Chanski and Petoskey wrestling coach William Arthur – were also denied the ability to opt out and filed grievances with MERC. The MEA eventually allowed the educators to leave the union, rather than proceed with the case.

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That’s likely because union officials realize they can no longer force school employees into union membership. If MERC officials had ruled in favor of Chanski and Arthur, it would have set a precedent that other educators would surely follow.

Lapham’s case could do the same, and it will be interesting to see whether MEA officials decide to let her go as well, or if they decide to play hardball and run the risk that MERC officials put an end to the “August window” once and for all.