Pat Little, Associated Press Penn State professor Michael Berube, in his office at University Park, concedes he's sometimes cheeky and snarky. Click photo for larger image.

STATE COLLEGE, Pa. -- Hockey is a bruising sport.

So are the campus culture wars.

It seems oddly appropriate, then, that some of the biggest body blows from the left these days are coming from a Penn State University scholar and amateur hockey player who's as comfortable slamming a puck into the net as he is dissecting the racial context of a James Baldwin novel.

As he lectures to his literature class, Michael Berube seems too genial to be one of America's 101 most-dangerous academics, a label placed on him in a book last winter by conservative activist David Horowitz.

But make no mistake, Dr. Berube's own book published this fall is a blunt counter-assault on Mr. Horowitz and others who say liberal professors in America are force-feeding radical-left views to impressionable students.

The book, "What's Liberal About the Liberal Arts?" reopens the debate about opinion in the classroom. And it has further cemented his standing as an academic whom conservatives love to hate.

Some of them "think I'm just Satan-spawned and I never quite get it," said Dr. Berube, 45, who seemed during an interview in his faculty office to catch himself mid-sentence in a bit of self-denial.

"OK," he said sheepishly. "Sometimes, I'm cheeky and snarky."

Mr. Horowitz would no doubt agree. In one heated debate between the two, Mr. Horowitz called his adversary a "fulminating leftist."

In his book, Dr. Berube doesn't dispute that liberals far outnumber conservatives in academia -- by almost three to one -- or that a few fringe professors on the left damage themselves by espousing extreme views. But he says liberal professors are increasingly under siege from a well-organized and politically connected movement that distorts figures, fabricates classroom injustices against conservative students and encourages the dissemination of their stories to sympathetic politicians and the news media.

He asks why conservative elites who decry "leftist" universities nevertheless send their own children to the Ivy League, Berkeley and Duke.

"Even culturally conservative pundits -- the kind who spend a good deal of ink decrying the state of American campuses -- know better than to ship their offspring off to Bob Jones University," he said.

A self-described "fast-talking, wise-cracking, pop-culture-loving" scholar, Dr. Berube is the Paterno Family Professor in Literature. He came to Penn State in 2001 from the University of Illinois and has authored half a dozen books as well a numerous essays and journal articles.

Being in the trenches of the culture war has placed him in the odd position of having a higher profile nationally than on his own campus.

An often-quoted commentator from the left, he's written for, or has been quoted in, publications ranging from the Village Voice to Salon to The New York Times, which reviewed his book.

Yet reaction to its release on the state's flagship public campus has been "pretty muted," he said, and a book signing in the Penn State bookstore wasn't advertised in the campus newspaper. "Only a handful of faculty and students came by," he said.

To illustrate the unpredictable nature of liberal-arts instruction, Dr. Berube draws on his own classroom navigation of dicey situations, including one in which a student declared support for internment of Japanese Americans during World War II.

It's one thing to keep a chemistry lecture free of beliefs. It's another when the assigned reading for class touches on Jim Crow or sexual identity.

"It would be an abuse of my position if I were to treat my students as captive audiences who need to be educated about the rightness of affirmative action or the wrongness of Republican fiscal policy," Dr. Berube writes.

At the same time, he adds, "I would be selling students short if my classes did not reflect some of my beliefs about literary theory, or feminism, or postmodernism or multiculturalism, since I have spent my entire adult life studying such things."

Campus indoctrination has been a sensitive issue of late in Pennsylvania, which is among the states that have seen legislation aimed at exposing liberal bias. Those measures were inspired in part by Mr. Horowitz's "Academic Bill of Rights," which he describes as an attempt to take politics out of the classroom.

Last week, a Pennsylvania bipartisan House panel recommended after a series of hearings that colleges make sure students are familiar with campus policies on academic freedom. It found that actual cases of classroom bias were rare and not in need of new state rules.

Mr. Horowitz says if anything, it's Dr. Berube who's doing the attacking and that he "picks on sound bites" instead of discussing the real issue.

It's not about liberal bias because "everyone has bias. It's about the abuse of the classroom" and professors "who go off politically" in front of students who aren't on equal footing to challenge them.

"It's really about free speech," he said.

"You don't go to your doctor expecting to get a lecture on the war in Iraq. Why should you expect one from your English professor?"

Mr. Horowitz said that as soon as it was challenged, he retracted a claim that a Penn State professor had shown Michael Moore's "Fahrenheit 9/11" in class shortly before the 2004 presidential election. It was "just a good example that illustrates a problem."

"I have dozens, probably a hundred, examples," he said.

He cites a University of Colorado professor who set off a furor with an essay that characterized the Sept. 11 terrorist attacks as retribution for past U.S. military transgressions and called World Trade Center victims "little Eichmanns,'' in reference to Nazi war criminal Adolf Eichmann. Mr. Horowitz further points to a claim by a Kuwaiti student attending Foothill College in California that an essay defending the U.S. Constitution prompted a professor to tell the young Muslim he needed psychological help.

Stroll Penn State's main campus and it's hard not to encounter some type of belief-peddling, be it anti-war activists or the Willard Building preacher who, during one recent lunch hour, asked passersby, "Why aren't you getting your morals from God?"

But how often do claims of strident opinion become an issue in the classroom?

In response to the state House committee's bias investigation, Penn State reviewed five years of campus records through 2005. It found 13 complaints from students alleging liberal or conservative bias across its 83,000-student system, about half of them substantiated.

Noting that more than 177,000 courses were taught during that period on sometimes touchy subjects, "The numbers speak for themselves," said Blannie Bowen, Penn State vice provost for academic affairs.

Those isolated cases, though, often can escalate.

A Muslim student picketed his own class after becoming convinced that his Jewish political science professor was anti-Muslim. The charge was found to lack merit, but the instructor filed his own action against the student for leafleting and disrupting class.

Another student felt that single parents and gay partners were being left out of a faculty member's definition of family.

In yet another case, a parent contacted the school after a grad student teaching a course e-mailed students a link to a site that asked President Bush to fire the architect of his No Child Left Behind plan.

In interviews, students expressed varying views about how serious the problem is.

Seth Bender, 20, a junior from Lebanon, Lebanon County, who has been active in Penn State's student Republican Club, sometimes checks the voter registration of professors so he knows what he'll face in class. He recalled feeling oppressed by what he described as a political science professor's slanted comments that included jabs at President Bush.

"He would actually have a multiple-choice question that asks, 'Which of these countries do not have weapons of mass destruction?' You had to answer Iraq or you would get the question wrong.

"I don't think I would ever raise my hand in the classroom to confront him. He would make you look like a fool if you did," Mr. Bender said. "There were many times I wish I had a tape recorder in the classroom."

Others don't see as big a threat from the legions of liberal professors on campus.

"I've never seen a case where somebody from the far right comes into college and leaves a pinko," said senior William Wherry, 21, of Altoona.

In his own case, he said, sparring verbally with his professor in a Chicano literature class enabled him "to find weaknesses in my own arguments and repair them."

As long as it's properly disclosed by the professor, he said, "Bias is good."

One morning this fall, Dr. Berube's discussion of Mr. Baldwin's "Go Tell It on the Mountain" moved acrimony-free through mentions of sexual assault, Reformation, urban vs. rural life and Greek gods. But one subject -- a controversy over banning alcohol in parking lots during Penn State football games -- seemed too much for a professor who doesn't normally shy from debate.

"You'd think it was the great issue of our time," he said sarcastically. By the way, he told the class, pausing for effect, "I have no position on it."