Sen. Elizabeth Warren (D-Mass.) wrote a letter on Tuesday advocating for strong Federal Communications Commission privacy rules for internet service providers.

In the letter, which was addressed to FCC Chairman, Tom Wheeler, she asked for “strong FCC rules to establish clear consumer privacy standards for broadband internet access service (BIAS).”

According to Warren, the absence of clear and strong rules for BIAS providers has resulted in a host of dubious practices that endanger consumers’ privacy, and I am particularly concerned about new business models that single out low-income consumers for differential treatment with regard to their privacy and the use of their financial and other personal data.

She pointed out that internet access is an essential service, and people who do not have broadband   are at a disadvantage when it comes to keeping up with the latest news, getting information, or even searching for jobs.

Consumers had no choice than to disclose personal information to BIAS providers, giving them access to “vast troves of customer data, including search terms entered, websites visited and duration of those visits, location information, and enormous amounts of other data,” Warren noted.

BIAS providers are also engaging in practices that require consumers to pay extra fees so that their provider will not collect their data or sell it to third parties, she said. AT&T’s Gigapower Internet service requires consumers to pay as much as $66 in additional monthly costs for service that maintains their privacy, explained Warren.

She said the practices are “wrong,” and that “Privacy is not a luxury good reserved only for the wealthy.”

“We should not allow BIAS providers to extort consumers who want to control how their personal information is used and shared when they use essential communications services,” Warren added.

She urged FCC to speed up the adoption of stronger consumer privacy protection policies. “As the examples in this letter demonstrate, BIAS providers are continuing to develop new invasive and abusive practices using consumers’ private financial and other personal information. I therefore ask the Commission to adopt strong consumer privacy rules without delay.”

Internet service providers are worried that the rules will hurt potentially lucrative moves into digital advertising. The privacy proposal is expected to be voted on later this year.