Penn faces a choice between the easy world of groupthink, cliché and smug campus orthodoxies, or the challenging world of intellectual engagement and debate that leads to truth and understanding.

Princeton University wins praise for embracing intellectual diversity. The university preserved its principles, neither bowing to the Black Justice League to erase the memory of Woodrow Wilson from the campus, nor hiding the ugly history of Wilson’s disdain for African Americans. Incoming students read Keith Whittington’s Speak Freely: Why Universities Must Defend Free Speech. Princeton walks the walk.

Penn, meanwhile, persecutes a distinguished law school professor named Amy Wax for belief in the “bourgeois values” that shaped my generation, and for questioning whether Penn’s policy of racial preference does any good for the people it presumes to serve. Professor Wax is a Marshall Scholar, and earned a medical degree from Harvard and a law degree from Columbia, where she was editor of the Columbia Law Review. She has argued 15 times before the U.S. Supreme Court and has won three major teaching awards at Penn.

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Most recently, in a manner reminiscent of populist authoritarian regimes, the dean of Penn Law proclaimed Professor Wax’s view on immigration policy to be against Penn’s “core values.” When did Penn acquire an official position on immigration? The University of Chicago’s widely respected 1967 Kalven Committee warned: “There is no mechanism by which [the University] can reach a collective position without inhibiting that full freedom of dissent on which it thrives … The neutrality of the university … arises out of respect for free inquiry and the obligation to cherish a diversity of viewpoints.” Penn needs to wake up to best practices.

Penn disregards its own guidelines on open expression: “[T]he freedom to hear, express and debate various views, and the freedom to voice criticism of existing practices and values, are fundamental rights that must be upheld and practiced by the University in a free society.” I look back upon a once beloved campus and see oppression the likes of which I did not think possible.

Penn talks the talk, but can it walk? In response to a letter my colleague sent to President Amy Gutmann, protesting the treatment of Amy Wax, the provost had these self-satisfied words: “We are very proud of Penn’s historic tradition and active promotion of open expression, which we believe is at the heart of a great university … Indeed, this commitment was again recognized this year by FIRE (the Foundation for Individual Rights in Education), which gave Penn the highest rating for free speech along with only five other private universities …”

It doesn’t matter whether repression comes from the Left or Right. It has the same corrosive effect on minds and hearts.

Penn is hiding behind a pathetic Maginot Line. FIRE is pointedly clear about that, stating, “our speech code ratings do not take into account incidents of censorship or punishment levied against a student or faculty, or other actions taken by a university administration.” Penn cannot defend its actions.

Groupthink is an equal-opportunity disease. If we don’t want to emulate places like Princeton, the University of Chicago, Columbia and Purdue, which endorsed the University of Chicago’s Principles of Freedom of Expression and live by them, who, exactly, do we want to be?

We can be Middlebury College, disgraced by its shout down of Charles Murray and the injury inflicted on Professor Allison Stanger for agreeing to hold a discussion with him, and its recent encore of disinviting philosopher Ryszard Legutko. Or perhaps Liberty University, whose president, Jerry Falwell Jr., demands the party line on politics, school finance and governance.

It doesn’t matter whether repression comes from the Left or Right. It has the same corrosive effect on minds and hearts. Will Penn one day earn the kind of press that Falwell got from the Washington Post: “Inside Liberty University’s ‘culture of fear’”? As Professor Wax experienced, we are closer to that than you may think.

Penn is at an ethical crossroads. It must immediately offer a sincere apology to Professor Wax, lift the sanctions imposed on her by Law School Dean Ted Ruger, and once again give first-year law students the benefit of her superb teaching and scholarship. Otherwise, it’s on the easy path of political correctness, with all of its authoritarianism. It won’t be long before Penn will be not the peer of Princeton, but merely the progressive twin of Liberty University.

In the past, my wife and I have proudly donated over $10 million to an alma mater we love. We urge Penn’s leadership to remove the stain that now rests upon the university.

Paul Levy is a former member of Penn’s Board of Trustees and the Penn Law Board of Overseers.