By Dorothy Tucker

CHICAGO (CBS) — The Chicago Teachers Union will ask rank-and-file teachers, for a second time, if they want to authorize a strike.

The rank-and-file balloting will probably take place Sept. 21-23. The possible 2016 strike could be longer and uglier, CBS 2’s Dorothy Tucker reports.

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“Be prepared as much as you can,” said Alison Eichhorn, member of the union’s big bargaining team. This year could be worse than 2012, she said, describing it to be longer and harder.

In 2012 the strike lasted nine days. Eichhorn thinks it’ll be harder to reach an agreement this time because a proposed contract that CTU President Karen Lewis publically favored in January was unanimously rejected by Eichhorn and the 40 member bargaining team in February. Eichhorn said there’s been no new offer from CPS.

“I would consider they’e not serious about negotiating with us,” Eichhorn said. “And they need to get serious if they want to avoid a work stoppage.”

Union President Karen Lewis expects a near-unanimous vote in favor, but she said that does not guarantee a strike 10 days later. The specific date would be up to the House of Delegates and would be done “when it’s necessary,” Lewis said.

The board’s negotiators are running union proposals “up the flagpole,” but the board has to come back with something different, Lewis said. Ideally, something that includes no pay cuts by their definition, and no program cuts.

Wednesday’s vote by the House of Delegates asking teachers to take another strike vote was a sign that teachers are preparing for a strike. But this time, instead of a private ballot, teachers were asked to sign a public petition.

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Eichhorn said signing a public petition is like walking a public picket line. She thinks it is fair to make teachers publically sign and show their vote.

“If you do not want to sign you respectfully tell your delegate I do not want to sign and there will be no repercussions,” Eichhorn said.

A retired teacher disagreed.

“It could bring bad blood among teachers,” said Willie Pickens, retired teacher. “Like you did not sign, so you are against us.”

A teacher delegate from the Nettlehorst School, Michelle Gunderson, said she has 27 students in her classroom. Teachers are leaving the system “by the droves” because of more favorable conditions in suburban schools.

A teacher delegate at the Jenner School, Tara Stamps, said that she has 42 students in a class and education at the school is in “a sad state.”

The teachers last struck four years ago. They continue to work under terms of that contract, which expired in June 2015.

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This is the second time teachers have taken a strike authorization vote. More than 90 percent of teachers voted in favor of the strike in December.

Dorothy Tucker