NYT Editor Complained About Opinion in News Stories

The Standards Editor of the New York Times,  Allan M. Siegal, made an interesting admission in an interview with his own publication today:

I'm supposed to be the recipient of any complaints and misgivings by the staff about how we're doing and what we're doing, the person who adjudicates differences of opinion about how we should go about reporting and editing stories.

By the charter that my job was given when it was set up, I have the guaranteed right to go not just to the executive editor with any misgivings I have, but directly to the publisher. On one occasion, when I thought that there was too much opinion seeping into the news pages, I went to both of them simultaneously. But that's the only time I've felt it necessary to involve the publisher.  [emphasis added]

As Jeff Jarvis asks, what was that occasion?