SPRINGFIELD, Ill. — What might appear as a snit over losing out on a $500 teaching award has escalated into a University of Illinois professor's fight for his professional life, in what he describes as a quest to vanquish an authoritarian administration and what school administrators say is an unprecedented attempt by trustees to remove him.

Engineering professor Louis Wozniak could find out Thursday whether the university's board will revoke his tenure for a list of charges including harassing a student, improperly obtaining and publishing grades, and sending an email to students that included a sexual reference. It would end a career with the university that's lasted half a century.

A spokesman says U of I officials are unaware of any other cases in which an attempt by the university to fire a faculty member reached the board. Members are scheduled to take up the decision at their meeting in Springfield.

How Wozniak got to this point baffles some. But the 75-year-old immigrant, who spent his early years in an Italian orphanage after he says his father was killed by Nazis and his mother died shortly thereafter, describes it in the quixotic terms befitting his hardscrabble beginning.

"It's not just a matter of $500, which is parking meter money, or an award that I really don't need," said Wozniak, who has been suspended with pay from his $85,000-a-year job for more than three years. "It's a matter of principle.

"Somebody's got to stop these [administrators] somewhere, because the next time around, you will have a grant from NSF [National Science Foundation] and you will be principle investigator that had the idea, but what's going to happen is, the department head will assign it to someone else. How far can you be pushed?"

The administration filed eight charges against Wozniak. But a faculty review committee, while describing him as "self-righteous, obsessed and insensitive," found Wozniak only erred in one area and said a three-year paid suspension was penalty enough.

Still, the administration persisted.

"He refuses to accept valid constructive criticism, is indifferent to the harm and suffering his conduct brings to others, and has proven he cannot and will not conform his conduct to the professional standards expected of tenured faculty members," U of I president Robert Easter wrote to the board in a document Wozniak provided.

Wozniak's problems began in 2009 when he was passed over for a student-administered teaching award after receiving the most votes. The award, which Wozniak had won previously, is given by two engineering fraternities and was traditionally presented to the top vote-getter after graduating seniors were polled.

This time, students — in consultation with a department official — awarded the $500 prize and a plaque to someone else.

Wozniak is charged with harassing one of the students involved in the award by publicizing a private conversation the two had, improperly disclosing a grade he gave her, and other offenses — including the one that got him suspended in 2010. That involved an email to graduating seniors that jokingly referred to having had sex with some of his "adorable GKs," referring to "grandkids," a nickname he bestows on students. He apologized the next day in a follow-up message and told superiors he'd never had sex with any students.

That wasn't the professor's best moment, said former student Tim Seiwart, a 2004 graduate who is now a civil engineer with a Chicago-area construction company. But Wozniak's overall approach in the classroom taught students how to ask questions and solve problems, Seiwart said.

"If you don't push the boundaries a little bit, you're never going to get innovation," Seiwart said. "His problems are with the administration, but his approach pushed students above and beyond and that's what leads to technical innovation. That's what we are all paying to go to school for."