The Senate Commerce Committee will question executives from broadband providers as well as major tech companies at an upcoming hearing on privacy, the committee announced Wednesday.

“Consumers deserve clear answers and standards on data privacy protection,” Senator John Thune (R-South Dakota) stated. “This hearing will provide leading technology companies and internet service providers an opportunity to explain their approaches to privacy, how they plan to address new requirements from the European Union and California, and what Congress can do to promote clear privacy expectations without hurting innovation.”

Witnesses from AT&T, Amazon, Google, Twitter, Apple and Charter are expected to testify at the hearing, which will occur on September 26.

The hearing comes several months after California enacted new privacy legislation that allows consumers to learn what personal information about them is held by businesses, and to opt out of the sale of that information. That law is slated to take effect in 2020.

Soon after California passed the law, tech companies reportedly began pressing Congress to develop a federal privacy law that would trump individual state laws.

The list of expected witnesses doesn’t include any privacy advocates or consumer representatives — an omission flagged on Twitter by Gigi Sohn, who served as counselor to former FCC Chairman Tom Wheeler.

“Big online companies & broadband & cable companies who think they can get national #privacy legislation without participation from privacy & consumer groups are sorely mistaken,” she said on Twitter.

On Wednesday, the Silicon Valley trade group Internet Association endorsed the concept of a federal privacy blueprint, and weighed in with a set of proposed policy considerations for Congress.

“The time is right to modernize our federal rules and develop a national framework for consumer privacy,” the Internet Association stated. “That framework should be consistent nationwide, proportional, flexible, and should encourage companies to act as good stewards of the personal information provided to them by individuals.”

Among other recommendations, the Internet Association is backing a national data breach notification law that would preempt all state and local laws.

The organization is also proposing that privacy protections should be consistent online and offline, and “technology neutral.”

In addition, the Internet Association says a privacy framework should take into account the sensitivity of the information, the context of its collection, and the risk of “tangible harm” if the data is misused.