WHY THE KILLIAN STORY MATTERS. It's not that I'm rooting for Dan Rather. But I do think he deserves better than to be investigated by Dick Thornburgh, a former attorney general and Republican partisan with whom CBS has clashed in the past, as the New York Times reports. And why, Howard Kurtz's inside sources ask, is CBS News chief Andrew Heyward involved in setting up the investigation? Shouldn't he be one of the people being investigated?

An interesting side note to the matter of the fake Killian memos is why CBS News is falling apart over this when Fox, and to a lesser extent MSNBC, pay absolutely no price for pimping the false claims of Swift Boat Veterans for Truth. (I'm not going to repeat the case against the Swiftees except to note that their claims are contradicted by the official record, by the men with whom Kerry directly served, and, in several instances, by what the Swiftees themselves have said in the past. If you want more, go to the Daily Howler, which is in the midst of a lengthy, utterly convincing takedown of their book, Unfit for Command. And by the way, kudos to Fox's Bill O'Reilly.)

A good part of the answer, I think, is that the credibility of CBS matters and Fox's doesn't. Simple as that. Sorry, Roger, but Fox is little more than Republican-flavored infotainment, and it surprises absolutely no one when Sean Hannity - or, for that matter, a more respectable figure, like Brit Hume - keeps repeating stories that have already been proved false.

CBS News doesn't deserve to have the serious reputation it had in the days of Edward R. Murrow and Walter Cronkite. Maybe what happened with the Killian story is all too emblematic of the low standards that the former Tiffany network now embraces.

But obviously its reputation does matter. There's still an expectation of truth-telling on the part of CBS, and the fact that Dan Rather, Mary Mapes, and company now appear to be on the ropes is all the evidence you need to understand that.

BRUDNOY AND MEDIA LOG. I'll be appearing tonight at 8 on The David Brudnoy Show, on WBZ Radio (AM 1030), to talk about my book, Little People: Learning to See the World Through My Daughter's Eyes. I imagine we'll chew over the media and political scene, too.

NEW IN THIS WEEK'S PHOENIX. WBUR Radio (90.9 FM) has long been one of the most respected public stations in the country. But recent downsizing moves, including a sudden announcement that it intends to sell its Rhode Island affiliates, raise serious questions about what's going on at the station. It's time for license-holder Boston University to start demanding some answers.