This post is written as part of AOL Money & Finance's Best & Worst 2006. Vote for Patricia Dunn's fall from grace or see other nominees in this category.

If you were to look back at this year's biggest management foibles and try to rate the largest, which would you choose? How about former Hewlett-Packard Company (NYSE:HPQ) chair Patricia Dunn? I would count her as the company leader who fell from grace hardest this year. The former chairwoman of one of Silicon Valley's most respected companies was embroiled -- and still is -- in a corporate spying scandal, as the former chair tried to ferret out press leaks from inside her own board of directors. She subsequently quit her post and was grilled on Capitol Hill in front of the U.S. Congress -- and the situation is not resolved yet.

Dunn seemed to be on a roll when she received the Financial Woman's Association of San Francisco's "Financial Woman of the Year" award in 2001, and when she subsequently succeeded Carly Fiorina as CEO of HP. But resigning as chair of the board in September didn't stop her from being charged in October by the state of California on four felony charges, including conspiracy and identity theft. If the scandal and the indictments weren't enough, Dunn, a survivor of both breast and ovarian cancer, discovered that the latter cancer had returned. She continues to undergo treatment.

From one of the top positions in the tech industry to a beleaguered witness, Patty Dunn gets my vote as the hardest-hit, "fallen from grace" corporate executive of 2006.