The story behind Jane Mayer's story about Dianne Feinstein
Jane Mayer says her story for The New Yorker about Senator Dianne Feinstein's "missteps" exposed one of the Senate's open secrets. Brian Stelter asks Mayer how she handled rumors of "cognitive decline," and Mayer says "this is an issue that used to be swept under the rug. I really don't think it can be anymore." And "given the aging of our current leaders," she says, "it's going to be something you'll see more of."