Brian Williams and NBC News

NBC Newsman Brian Williams announced in a note to news staffers that he is taking time off from the program. "In the midst of a career spent covering and consuming news, it has become painfully apparent to me that I am presently too much a part of the news, due to my actions. As Managing Editor of NBC Nightly News, I have decided to take myself off of my daily broadcast for the next several days," Williams wrote. He concluded, "Upon my return, I will continue my career-long effort to be worthy of the trust of those who place their trust in us."

Williams' announcement came one day after NBC News executives confirmed they are conducting an internal investigation into false claims made by Williams that he has since corrected. Williams admitted on his broadcast Wednesday night that, "I made a mistake in recalling the events of 12 years ago...I want to apologize."

For more than a decade, Williams has repeatedly said, that while on assignment in Iraq in 2003, he was aboard a helicopter that was hit by enemy fire and forced down. In March 2013, he told David Letterman, "We were going to drop some bridge portions across the Euphrates so the third infantry could cross on them. Two of our four helicopters were hit by ground fire including the one I was in. RPG and AK-47's."

Stars and Stripes, which broke the story, reported that Williams and his crew were actually aboard a helicopter "that was about an hour behind the three helicopters that came under fire." It quoted the helicopter's flight engineer, "No, we never came under direct enemy fire to the aircraft."

But now NBC News and Williams are coming under direct fire. Meanwhile, new allegations of fabrications by Williams have surfaced, which NBC News is now investigating. This crisis presents management with a nightmare dilemma.

NBC Nightly News with Brian Williams is currently the number one rated network evening newscast in households, and in the key 25-54 demographic, according to Nielsen. But ABC's World News Tonight is close behind and positioned to move ahead should NBC falter. The New York Post quotes figures from Kantar Media that show Nightly News made about $200 million in annual ad revenue in 2013, $30 million more than ABC's World News. NBC News executives are carefully watching the ratings to see how the audience responds to the controversy. A ratings reduction could cost the division millions of dollars and lead to layoffs.

While working as a reporter for the CBS local New York affiliate earlier in his career, Williams aspired to be Walter Cronkite, once America's "most trusted" newsman. In 1993, Williams joined NBC News, and he became anchor and managing editor of NBC Nightly News in December 2004. He replaced the legendary and beloved Tom Brokaw as the face of NBC News. Since his ascendancy, he has been a popular broadcaster and an award winning journalist. NBC News has vigorously promoted Williams as the leading news personality. So replacing him would be difficult.

Brokaw, in an email to the Huffington Post, denied a New York Post report he wanted Williams fired. "I have neither demanded nor suggested Brian be fired," Brokaw wrote. "His future is up to Brian and NBC News executives." In a memo to staffers Friday, NBC News president Deborah Turness said, "We're working on what the next best steps are--and when we have something to communicate we will of course share it with you." Neither statement expressed support for Williams.

The mistakes Williams has admitted to, and apologized for, have cast a dark cloud over everyone at NBC News. The news organization is filled with dedicated, hardworking and accomplished producers, reporters and technicians. This controversy has been devastating, disruptive and discouraging for everyone at NBC News, which has already had its share of struggles over the past few years.

While some critics have called for Williams to be fired, he still has many supporters, including within the organization. NBC News won't make a decision on his future until it has completed its investigation. If Williams continues to anchor Nightly News, he owes his viewers and his colleagues a better explanation than he has offered thus far.

Nonetheless, NBC News should be transparent with the findings of its internal investigation, and publicly release all of the facts it uncovers. Not to do so would severely undermine its credibility and cast doubts on its commitment to the highest standards of journalism.