CHICAGO (CBS) — Thirty-one principals in the Chicago public schools are sending a message to teachers’ union president Karen Lewis today.

They are weighing in on one of the issues in the contract dispute between the teachers and the school board.

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In a letter to Chicago Teachers Union president Karen Lewis, the principals say it’s imperative that they have the autonomy to hire teachers they view as the most qualified.

That’s one of the unresolved issues that led to the teachers’ strike.

The union wants priority given to laid off teachers who lose their positions when an under-performing school is overhauled.

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Mayor Rahm Emanuel wants hiring decisions in the hands of principals, not the union or the central office.

“I don’t think downtown should be in the business of selecting teachers. Local school principals should select if you’re going to hold them accountable,” Emanuel said on Tuesday.

The school district released a copy of the principals’ letter to the media.

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