The Chicago Teachers Union may paint the town CTU red as they did in 2012 if they strike this fall. But they could be joined by a big splash of SEIU purple.

The other major union in Chicago Public Schools (CPS), Service Employees International Union Local 73, representing 7,000 special education classroom assistants, custodians, bus aides, and security guards, is also without a contract, and its members voted by a wide margin this summer to authorize a strike if they don’t get a living wage and protection against privatization.

Like the CTU, Local 73 argues that members’ struggle is about more than dollars and cents — it’s a fight for the schools that Chicago’s students, teachers, and staff deserve. But in a union where the average member working in CPS makes around the amount that the federal government classifies as a very low income for a family of two in the Chicago area, the dollars and cents matter, too.

Both SEIU and CTU report disappointment in negotiations with the city, now led by new-mayor Lori Lightfoot, who claims she wants to improve conditions for working Chicagoans. In mid-September, SEIU will get the findings of a fact-finder’s report that could side with the union — or set the stage for a strike, if Local 73 rejects it.

Before this year, the two unions often found themselves at odds. In 2012, while a showdown between the CTU and hated former-mayor Rahm Emanuel was coming to a head, Local 73 signed an early agreement that teachers and some SEIU members thought undermined a united fight that could have won more for everyone.

This year is shaping up differently. Over the summer and during the first week of school following Labor Day, CTU and SEIU leaders stood together at rallies and press conferences, and members walked each other’s informational picket lines. Last week, the CTU’s governing body, the House of Delegates, set a date for a strike authorization vote, but Local 73 has already held its strike vote — and it was a resounding yes. The union easily surpassed the restriction in an undemocratic state law requiring 75 percent of the entire bargaining unit, not just those who vote, to authorize a strike in Chicago schools: 84 percent of Local 73 members cast a ballot — and of those, 97 percent voted to walk.

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