Education Secretary Arne Duncan called for dramatically raising teacher pay last Friday on MSNBC, declaring that the current average salary (about $55,000) should be doubled to improve teacher quality. It’s a familiar refrain for Duncan, who in the same interview declared himself a “radical” when it comes to paying teachers more.

Leaving aside whether the federal government should have any say in how local school districts pay their teachers, Duncan’s position is unwise. According to a recent study by The Heritage Foundation, public school teachers already receive total compensation (wages and benefits) greater than what they could earn, on average, in the private sector. So if the current compensation premium has not improved teacher quality, how would further increases do so?

Duncan is obviously aware of the Heritage study, since he took the time to denounce it on both the Huffington Post and his personal blog. That denunciation, however, was driven by his less-than-objective reaction to evidence that, in his words, “insults teachers and demeans the profession.” The American Enterprise Institute’s Rick Hess (unaffiliated with the study) called Duncan’s commentary “an unusual, personal attack.”

Duncan’s reaction to the Heritage study is especially disappointing given his reputation as a pragmatic reformer. “The path to real reform begins with the truth,” he stated in 2009 during an education forum with the Data Quality Campaign. We agree: Let’s all be consistent in pursuing evidence-based reform.