News of Facebook's secret tool to delete executive messages caps days of chaos

As Sheryl Sandberg mounts apology tour, company is under fire again over special privacy privileges not granted to regular users

When Sheryl Sandberg, Facebook's chief operating officer, embarked on a media apology tour Thursday, it seemed possible that the woman known as Mark Zuckerberg's "adult supervision" would bring calm to the troubled company's image.

But the past 48 hours have shown that not even Sandberg's steady hand can keep this car from spinning out of control.