Whenever a newspaper dies, Google turns up on the list of suspects.

The evidence of Google's involvement tends to be sketchy. A close examination of the crime scene typically points to a different villain -- the classified revenue killer known as Craigslist, parasitic news sites that siphon potential visitors, declining subscription and ad revenue, management that can't adapt, or the hyper-competition created by the Internet's ability to collapse distance and divert attention.

But Google nonetheless has been forced to defend itself. In May, Marissa Mayer, Google's VP of search products and user experience, testified before the Senate Subcommittee on Communications, Technology, and the Internet that Google is the hand that feeds media companies, channeling over one billion clicks every month to online publishers through Google Search and Google News.

She suggested that Wikipedia, with its constantly updated articles, might offer a better model for journalism in the Internet age than a series of separate articles. And she proposed that online publishers might be failing their readers by presenting them with Web pages that lack engaging social features.

At the Web 2.0 Summit panel discussion last month, Mayer delivered a similar message, that Google is friend and not foe to publishers.

But Mayer's olive branch was rebuffed by fellow panelist Robert Thomson, managing editor of Wall Street Journal. "Google wants to be the home page. It wants to be the front page. And Marissa unintentionally encourages promiscuity," he said.

It was a provocative instance of metonymy -- Mayer standing for Google -- that impugned by double entendre, even as Thomson revealed the real gripe of the old guard: Google News threatens the newspaper editor as the arbiter of what's newsworthy.

It's about the money too, of course, but that follows from influence and respect. News organizations that spend a lot on reporting don't want to be lumped into the same basket as all the other news outlets that write reports based on their reporting. They chafe at the sight of bloggers who quote their reports liberally, add two cents, and collect more than that in Google AdSense revenue.

Google has been addressing these issues for years now. Last week, it took another step to improve the quality of Google News through its guidelines for Google News Sitemaps, files published by news sites to help Google index their content. The revised guidelines require that news publishers label content PressRelease, Satire, Blog, OpEd, Opinion, or UserGenerated, if appropriate.

Google doesn't explain why it wants this information. But presumably these identifiers can be used to help make sure a blog post or Wikipedia entry isn't being featured in a prominent position on Google News at the expense, say, of a Wall Street Journal article.

A Google patent application filed last week provides a clearer explanation of the company's goals for Google News.