• by Wendy Davis  @wendyndavis, April 24, 2013

The head of the Senate Commerce Committee came out swinging at the online ad industry on Wednesday, accusing it of failing to honor an agreement to honor consumers' requests to avoid online data collection.

Sen. Jay Rockefeller (D-W.Va.) said at a hearing on Wednesday that the online ad industry has failed to live up to a promise made at the White House last year to respect do-not-track headers -- signals sent by browsers that tell Web sites users don't want to be tracked.

“Advertising folks are continuing to ignore do-not-track headers,” Rockefeller said at the hearing. “There's a broad feeling that the advertisers and data brokers are just dragging their feet. I believe that they are. And I believe they're doing it purposely.”

Earlier this year, Rockefeller and Sen. Richard Blumenthal (D-Conn.) reintroduced a bill that would prohibit online companies and app developers from collecting "personal information" from consumers who activate a do-not-track mechanism. The proposed Do Not Track Online Act of 2013 directs the FTC to develop regulations to implement a do-not-track tool.

Rockefeller repeated his call for legislation on Wednesday. “I do not believe that companies with business models based on the collection and monetization of personal information will voluntarily stop those practices if it negatively impacts their profit margins,” he said in his opening statement.

For the last two years, the Internet standards group World Wide Web Consortium has been trying to forge an agreement among computer scientists, privacy advocates and ad industry representatives about how to interpret the signals. But the effort so far hasn't resulted in any consensus.

Lou Mastria, managing director of the umbrella trade group Digital Advertising Alliance, said its agreement to honor do-not-track headers was “short-circuited” by recent privacy-related decisions made by Microsoft and Mozilla.

The DAA originally said it would honor browser-based headers, provided that users activated them. But last May, Microsoft announced that it turn on do-not-track headers by default in Internet Explorer 10. The DAA responded by reminding everyone that it never agreed to honor requests that weren't set directly by users.

Mozilla said in February it would explore a software “patch” that will automatically block third-party cookies -- like the cookies set by ad networks. Mastria said at the hearing that Mozilla's move doesn't reflect a choice by consumers.

Mozilla general counsel Harvey Anderson said at the hearing that the company is still evaluating how to handle third-party cookies. But Anderson also called it “specious” for the ad industry to blame Mozilla for holding up progress on browser-based headers, given that the most of the industry has ignored the headers since Mozilla began offering them two years ago.