So why is Phil Murphy, the likely Democratic nominee for governor, ready to tap the brakes on this success story? 

Murphy is a board member of the NAACP, the sclerotic civil rights organization, which is considering a resolution on Saturday to freeze the expansion of charter schools nationwide. As of Thursday evening, Murphy would not say where he stands on it. 

That’s not the first bad sign. Murphy said earlier this year that local school boards should be granted more power to block the establishment of new charter schools. That’s like giving General Motors the power to block Chrysler from building a new plant. In most school districts it would be tantamount to a moratorium… 

The most charitable explanation is that he is searching for common ground in the charter wars, and wants to establish himself as a neutral arbiter. It could be that he doesn’t know the issue well, a sign that his lack of political experience comes with a cost. 

But there is a darker possibility. Murphy could be selling out to the state’s largest teachers union, the New Jersey Education Association, which recently endorsed him. The NJEA is hands-down the most powerful special interest group in the state, always in the top ranks in lobbying and campaign spending. And it has done all it can to kneecap the charter school movement, which relies mostly on non-union labor. 

Murphy filled out a questionnaire to get the union’s endorsement. But he will not release his answers, bowing to the confidentiality request of the union. 

That is a rookie mistake. The union is not his master, and he is free to discuss his views on charter schools, with or without union permission. His refusal to do so says, in effect, that the union has a right to know his views but the public does not.