Paul Chellgren knows a thing or two about the importance of business ethics.

But in his new gig at Northern Kentucky University, it's doubtful he'll be sharing.

Last year, the Harvard grad retired as CEO of Ashland Inc., Kentucky's second-largest corporation, after having an affair with a subordinate in violation of company policy. In his severance deal, he agreed to excuse Ashland from any lawsuits that might arise from the relationship.

Chellgren led an $8.5 billion corporation as it spun off its oil business and expanded into other realms.

He knows business. He also knows the pitfalls of personal transgression.

Guess which topic he's avoiding.

Loves teaching

Last year, the former chief executive officer called NKU President James Votruba and mentioned his interest in teaching on a volunteer basis. The offer pleased Mike Carrell, dean of the business school.

"To have someone with his experience come in and teach strategic management is just great," Carrell told me. "You'd like to have a dozen people in the classroom with that kind of experience."

The circumstances of his departure from Ashland were irrelevant, the dean said.

"That related to a policy of Ashland's and not to any law or other violations," he said. Besides, other adjunct faculty are not questioned about past relationships before they are hired.

Chellgren is now in his fourth week of teaching what's supposed to be the capstone course for MBA students, tying together all they've learned previously.

I caught up with Chellgren this week. He loves the classroom, he said, and is making time for it between business trips around the country. (He declined to elaborate on those.)

"I can tell them what it's really like in the boardroom," Chellgren said enthusiastically. "I can tell them what it's really like in an audit committee."

And the missteps that led to his retirement?

He winced.

"That's my personal business," he said.

Any of us would probably react the same. The question is whether NKU did right by accepting his services so soon after the scandal.

"I'm not sure we would hire such a person here," said John Boatright, professor of business ethics at Loyola University in Chicago. Students might get the message that personal conduct doesn't matter if you're a business executive, Boatright said.

Another ethics professor begged to differ.

We choose doctors based on their ability to heal, not on their affairs, said Daryl Koehn of St. Thomas University in Houston. Why should business teachers be judged differently?

Many of Chellgren's students know about his screw-up. Some told me he has a lot to offer, regardless.

I can believe that. But beyond the dry facts of management, he has an insider's perspective on how not to run things.

That would be one heckuva lecture. Too bad no one will hear it.

E-mail kgutierrez@enquirer.com, or call (859) 578-5584.