The Senate Committee on Commerce, Science and Transportation conducted a hearing about online privacy at which Federal Trade Commission Commissioner Julie Brill testified, supporting the idea of a Do Not Track mechanism both online and on mobile devices.

Brill told senators at the hearing on “Privacy and Data Security: Protecting Consumers in the Online World” that the FTC has brought more than 300 privacy-related actions, including spam cases, data security cases, Fair Credit Reporting Act cases, spyware cases, and cases enforcing the Children’s Online Privacy Protection Act.

Referencing the FTC’s December 2010 report on privacy, Brill said the FTC recommended a “privacy by design” approach to regulating privacy, including the use of a Do Not Track mechanism.

“Any Do Not Track system should not undermine the benefits that online behavioral advertising has to offer, by funding online content and services and providing personalized advertisements that many consumers value,” Brill said.

The mechanism should be “flexible,” she added, and “should allow companies to explain the benefits of tracking and to take the opportunity to convince consumers not to opt out of tracking,” possibly including “an option that enables consumers to control the types of advertising they want to receive and the types of data they are willing to have collected about them, in addition to providing the option to opt out completely.”

The agency also recommended that companies should improve their privacy policies, Brill said.

Although fellow Commissioner J. Thomas Rosch voted to issue the testimony, he authored a separate statement recommending that both the FTC and lawmakers undertake an effort to learn more about Do Not Track before moving forward with such legislation, expressing concern that the parties are “acting blindly.”

“We must gather competent and reliable evidence about what kind of tracking is occurring before we embrace any particular mechanism. We must also gather reliable evidence about the practices most consumers are concerned about,” he said.

At the hearing, Sens. Rockefeller and Kerry also discussed their proposed privacy legislation. Sen. John Rockefeller (D-W.V.) introduced the Do Not Track Online Act of 2011 while Sens. John Kerry (D-Mass.) and John McCain (R-Ariz.) introduced the Consumer Privacy Bill of Rights Act of 2011. Sens. Kerry and McCain’s bill does not include a provision for a Do Not Track mechanism, but would require companies to inform consumers about their online collection practices and allow them to opt out of behavioral targeting.

In her testimony, Brill noted that the FTC has not advocated for a particular bill.

To read the text of Commissioner Brill’s testimony, click here.

To read Commissioner Rosch’s statement, click here.

Why it matters: The Committee hearing evidences the continued push for privacy legislation in Washington and the continuing divide over the need for a Do Not Track mechanism, with both the FTC and lawmakers split on whether it is a necessary piece of privacy protection. Advertising groups and privacy and consumer rights organizations contributed to the hearing via letters, advocating for and against Do Not Track. In their letter to the Committee, the U.S. Chamber of Commerce, the Interactive Advertising Bureau, and other ad associations weighed in on behalf of continued self-regulation. “Any government restriction on the ability of companies to gain revenue from advertising would result in less free or subsidized content being made available to users and would inhibit innovative start-ups,” the groups wrote in their letter. On the other end of the spectrum, consumer advocacy organizations such as the Electronic Frontier Foundation, the ACLU, and the Center for Digital Democracy argued in a letter that “technology has outpaced the law. . . . Consumers have no meaningful ability to limit the use of their personal information that they provide to companies online.”