Education Secretary Betsy DeVos speaks at the Conservative Political Action Conference (CPAC) in Oxon Hill, Md., Thursday, Feb. 23, 2017. (Susan Walsh/AP Photo).

U.S. Education Secretary Betsy DeVos delivered her most extensive comments to date on higher education Thursday at the Conservative Political Action Conference in Maryland, criticizing professors and deans for indoctrinating students.

"How many of you are college students?" DeVos asked a receptive audience before criticizing professors for telling students what to say and what to think.

“They say that if you voted for Donald Trump you’re a threat to the university community, but the real threat is silencing the First Amendment rights of people with whom you disagree,” DeVos said.

DeVos also urged conservative students to speak out.

American Conservative Union (YouTube)

“Don’t shut up,” DeVos advised. “Keep talking. Keep making your arguments. You can do so respectfully and with civility but I think you need to do with confidence. We need to have opposing viewpoints and differing ideas in an academic environment and in any environment where idea are necessary to be exchanged."

While studies show many professors lean left, academics dismiss DeVos's accusation as red meat politics.

Sociology lecturer Josh McCabe runs a program on ideological diversity at Wellesley College and he says the Secretary’s remarks oversimplify today’s campus climate.

“We’ve all got anecdotal stories about professors who preach more than they teach, but most professors really are just dedicated social scientists interested in finding the truth not in ideological indoctrination,” McCabe said.

McCabe worries DeVos’s generalizations are part of a broader agenda to de-legitimize institutions perceived as critical of the Trump administration.

Earlier: At Wellesley, A Conservative, A Libertarian, And Some Liberals Walk Into A Classroom