WASHINGTON — Texas Attorney General Ken Paxton is leading a group of 50 attorneys general in filing an antitrust probe into Google’s business practices.

The investigation will look into whether Alphabet Inc, the parent company of Google and its subsidiaries, monopolize the online advertising and search engine markets while using private user information. Paxton announced the preliminary investigation on the steps of the U.S. Supreme Court building Monday afternoon, accompanied by 13 other attorneys general who are part of the bipartisan coalition.

Paxton’s spokesperson, Marc Rylander, called the investigation “nearly unprecedented." Every U.S. state and territory is represented in the group, with the exception of Alabama and California.

Though Paxton said Google is presumed innocent until the investigation is complete, he accused them of using their size to stifle competitors and consumer choice. However, no potential remedies were discussed.

“While many consumers believe the internet is free we know that the internet is not free,” Paxton said. “This is a company that dominates all aspects of advertising on the internet and searching on the internet.”

A subpoena to Google has been filed as of Monday but the details of what information was requested is unknown. The timeline of the investigation has also not been determined.

The European Commission has filed several antitrust actions against Google in the past, and just last week the Department of Justice requested records from prior antitrust investigations.

The announcement of the investigation came the week Congress returns from recess. When asked, Paxton said the decision was not meant to send a message to federal lawmakers.

But in June, Paxton and 41 other state attorneys general filed a bipartisan comment to the Federal Trade Commission urging a renewed focus on consumer privacy and data in antitrust enforcement actions against dominant technology platforms, such as Facebook and Google.

The Federal Trade Commission has previously investigated Google’s search and advertising businesses for violations of antitrust law, but regulators there concluded their probe in 2013 without issuing major punishments against them.

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