Rahm Emanuel / Washington Post

After being widely expected to ratify a deal with the Chicago Public Schools on Sunday, the Chicago Teachers Union voted instead to weigh the offer for a few more days. Mayor Rahm Emanuel responded by taking legal action, insisting that the strike was "illegal on two grounds – it is over issues that are deemed by state law to be non-strikable, and it endangers the health and safety of our children." Is he right? Is the strike illegal?

It all depends on your reading of Illinois state's laws regarding public employee unions (hat-tip Ramsin Canon). Here's the language on the "health and safety" of Illinois children:

If, however, in the opinion of an employer the strike is or has become a clear and present danger to the health or safety of the public, the employer may initiate in the circuit court of the county in which such danger exists an action for relief which may include, but is not limited to, injunction. The court may grant appropriate relief upon the finding that such clear and present danger exists. An unfair practice or other evidence of lack of clean hands by the educational employer is a defense to such action.

Emphases mine. So if Rahm can show that the costs of the strike in terms of lost instructional time and lost access to school health services like nurses and social workers endangers the city's children, a judge can issue an injunction to stop the strike.

The "lack of clean hands" defense, however, is relevant. Generally in civil law, a plaintiff must be innocent of wrongdoing in the issue being litigated in order for their lawsuit to be considered. This opens up space for the Chicago Teachers Union to argue that Emanuel and the school systems' intransigence caused the strike, and thus their hands are not clean and thus caused the strike.

But the standard for wrongdoing is high. The burden of proof for determining that the plaintiff is at fault rests with the defense, so all Emanuel needs to show is that there is no evidence that he didn't have the district's children's best interests in mind, or that he committed an unfair labor practice. If, on the other hand, CTU presents compelling evidence that a labor infraction occurred, Rahm's toast.

What about the "strikable issues" claim? Section 4.5 of the Illinois Education Labor Relations Act lays out what issues are eligible for collective bargaining, but which are to be resolved exclusively through a mediation procedure "in lieu of a strike":

(2) Decisions to contract with a third party for one or more services otherwise performed by employees in a bargaining unit and the procedures for obtaining such contract or the identity of the third party.

(3) Decisions to layoff or reduce in force employees.
(4) Decisions to determine class size, class staffing and assignment, class schedules, academic calendar, length of the work and school day with respect to a public school district organized under Article 34 of the School Code only, length of the work and school year with respect to a public school district organized under Article 34 of the School Code only, hours and places of instruction, or pupil assessment policies.

(5) Decisions concerning use and staffing of experimental or pilot programs and decisions concerning use of technology to deliver educational programs and services and staffing to provide the technology.

Emphases mine. This seems to rule out teacher evaluation policies, recall policies, school closures and ensuing layoffs, the length of the school day and school year from the list of strikable policies. But it leaves teacher compensation as a strikable issue, and given that negotiations are still touching on the size of raises over the next four years, in the light of Emanuel's rescinding of a promised pay increase in the last school year. Even if if takes most strike issues off the table, it's not obvious that it should rule the strike as a whole illegal so long as raise issues remain.

So the "clear and present danger" argument seems a more promising avenue for Rahm than the strikable issues claim. But still, the empirical burden of proof there is weighty. While there exist studies suggesting that strikes, insofar as they reduce instruction, reduce student achievement, CTU could try to poke holes in those or dispute that the standardized tests upon which they are based constitute valid evidence. It could also reasonably argue that if the strike endangers students, regular vacations must as well. Though summer learning loss is a real problem, it seems unlikely that courts would rule vacation a danger to students.

Rahm's case, then, is anything but a slam dunk. And even if he wins in court, that won't change the fact that a huge majority of Chicago public school teachers voted to strike, and presumably won't stop making trouble for him after they return to work.