After a long public battle and weeks of protests, the janitorial contract at Chicago's O'Hare International Airport changed hands in late 2012 (see reports here). Some reports claimed the move was based on relationships between the new contracted company and Chicago Mayor Rahm Emanuel. But no matter the reason, the shift arguably displaced over 300 workers that were part of the Service Employees International Union (SEIU).

In exchange for those SEIU employees, The Chicago Sun-Times reports that the new custodial workers at the airport will now be part of the Teamsters. The move raises eyebrows once again, since the Teamsters were one of the few unions that supported Emanuel’s 2011 mayoral campaign.

As reported the the Sun-Times, SEIU leaders — who were neutral in the 2011 mayor’s race and have since criticized Emanuel frequently — filed a complaint Thursday with the National Labor Relations Board. They say the city’s new airport janitorial contractor, United Maintenance Cos. Inc., “unlawfully coerced” its airport employees to become Teamsters.

Nora Kelley, chief of staff at SEIU Local 1, said United Maintenance and city officials refused to arrange access to the workers for SEIU to try to organize them. “Instead, they granted preferential access” to the Teamsters, Kelley said.

A representative for United Maintenance did say that the company’s O’Hare workers voted last week to join Teamsters Local 727 and that city officials played no role in the negotiations.

Asked about charges that City Hall favored the Teamsters, Emanuel spokeswoman Sarah Hamilton replied in an email that the matter is “a dispute between two labor organizations.” She added that the city “supports the rights of the employees of United Maintenance to bargain collectively.”