"Google's consolidation of its privacy policies potentially touches billions of people worldwide," the lawmakers wrote in a letter to Google CEO Larry Page. "As an Internet giant, Google has a responsibility to protect the privacy of its users. Therefore, we are writing to learn why Google feels that these changes are necessary, and what steps are being taken to ensure the protection of consumers' privacy rights."
The changes would allow Google to share information between its services. Users could begin seeing advertisements in Gmail based on videos they watched on YouTube, for example.
In an email to Google users on Thursday, the company said the changes will allow it to tailor its services to individual users.
"If you're signed into Google, we can do things like suggest search queries — or tailor your search results — based on the interests you've expressed in Google+, Gmail, and YouTube," the company explained. "We'll better understand which version of Pink or Jaguar you're searching for and get you those results faster."
The lawmakers asked Google to explain what information it collects, how its various services share information and what control users have over the information they provide to Google.
"While Google suggests that the purpose of this shift in policy is to make the consumer experience simpler, we want to make sure it does not make protecting consumer privacy more complicated," the lawmakers wrote.
They also said users should be able to opt out of the data collection.
The letter was signed by Reps. Cliff Stearns (R-Fla.), Henry Waxman (D-Calif.), Joe Barton (R-Texas), Edward MarkeyEd MarkeyWarren, Bush offer bill to give HHS power to impose eviction moratorium Overnight Energy & Environment — Presented by Climate Power — Senate Democrats ding Biden energy proposal Six Democrats blast Energy Department's uranium reserve pitch MORE (D-Mass.), Marsha BlackburnMarsha BlackburnHouse Oversight Democrat presses Facebook for 'failure' to protect users Warren, Daines introduce bill honoring 13 killed in Kabul attack Overnight Hillicon Valley — Scrutiny over Instagram's impact on teens MORE (R-Tenn.), Diana DeGette (D-Colo.), G.K. ButterfieldGeorge (G.K.) Kenneth ButterfieldHouse Democrats push to introduce John Lewis voting rights bill within weeks Black Caucus presses Democratic leaders to expedite action on voting rights Democratic clamor grows for select committee on Jan. 6 attack MORE (D-N.C.) and Jackie Speier (D-Calif.). Every member except Speier serves on the Energy and Commerce Committee.
Google defended the privacy changes and promised to work with lawmakers.
"People don’t need to log in to use many of our services, including Search, Maps and YouTube. When someone does log in to use our services, we give them ways to control how the information in their account is used. For example, they can use the Google Dashboard to see and control what information we associate with their account. They can also turn off search personalization, turn off or edit their search history, turn their Gmail chats to 'off the record' and use the Ads Preferences Manager to control how ads are tailored to them."
Lawmakers requested a response from Google by Feb. 16.
In a separate statement, Markey said he will ask the Federal Trade Commission (FTC) to probe whether the changes violate Google's recent settlement with the agency.
Google is required to abide by the terms of a settlement it reached last year with the FTC over charges that it mishandled user information with its now defunct Google Buzz social network.
The settlement bars Google from misrepresenting its privacy practices or changing the way it uses or shares consumer data without obtaining consent first.
— This story was updated at 4:42 p.m.