The U.S. Department of Justice has refused to assist French authorities in an investigation into X, according to a report citing a letter sent by the department’s Office of International Affairs.

The letter, dated Friday and reviewed by The Wall Street Journal, said the request from France raised concerns about potential conflicts with First Amendment protections, arguing the probe could amount to an attempt to regulate online speech through criminal enforcement.

French prosecutors have been investigating the platform for more than a year, focusing on allegations related to algorithmic practices and the handling of user data. As part of the inquiry, authorities in Paris reportedly searched X’s local offices earlier this year and sought to question CEO Elon Musk.

In its response, the DOJ said the request for assistance would risk entangling the United States in what it described as a politically sensitive case involving the regulation of a platform used for public discourse. The department emphasized that such actions could conflict with constitutional protections for free expression.

The investigation in France stems from complaints by lawmakers and advocacy groups who have raised concerns about whether X’s algorithms influence the visibility of content and whether user data has been handled improperly.

An official connected to xAI welcomed the DOJ’s decision, expressing hope that French authorities would reconsider the probe and ultimately drop the case.

Neither U.S. nor French officials provided immediate public comment following the report.

The dispute highlights growing tensions between U.S.-based technology companies and foreign regulators, particularly in Europe, where governments have taken a more aggressive approach to overseeing content moderation, data practices, and platform accountability.