Research & Developments is a blog for brief updates that provide context for the flurry of news regarding law and policy changes that impact science and scientists today.
On 9 March, a French researcher traveling to a science conference near Houston, Texas, was denied entry to the United States and expelled back to France. The scientist, on assignment for France’s National Center for Scientific Research (CNRS), was allegedly pulled aside for a random security check. U.S. authorities said they found private messages on the scientist’s devices expressing a personal criticism of the Trump administration’s treatment of scientists and scientific research.
Le Monde, the French news agency that reported the incident on 19 March, said that American authorities accused the scientist of sending messages “that express hatred towards Trump and can be qualified as terrorism” before confiscating their professional equipment. The researcher was also told of an FBI investigation, but that “charges were dropped.”
The U.S. Department of Homeland Security did not respond to requests for comment from multiple news outlets.
Philippe Baptiste, the French Minister of Higher Education and Research, declined to identify the researcher, saying only that they worked at CNRS in the space sector and were travelling to a conference near Houston. Space scientists deduced that the French researcher was likely traveling to the 2025 Lunar and Planetary Science Conference, which took place 10–14 March in Woodlands, Texas, about 30 miles north of Houston.
“Freedom of opinion, free research and academic freedom are values we will continue to proudly uphold,” Baptiste said in a statement. “I will defend the possibility for all French researchers to be faithful to them, in compliance with the law, wherever they may be in the world.”
Related
• French researcher denied entry to US for ‘expressing personal opinion’ on Trump policies (Le Monde in English and French)
• French scientist denied US entry after phone messages critical of Trump found (The Guardian)
• U.S. Turned Away French Scientist Over Views on Trump Policies, France Says (New York Times)
• Get Involved: AGU Science Policy Action Center
The French foreign ministry told France 24 that it “deplored the situation.”
Even before the incident, American scientists have been questioning whether it is still safe to travel overseas for conferences and worry they will be denied reentry or detained for exercising their right to freedom of speech. The American Astronomical Society’s Division of Planetary Science meeting will be in Helsinki, Finland this year and AGU’s 2026 Ocean Sciences Meeting will take place in Glasgow, Scottland. Likewise, non-American scientists have said they might skip professional travel to the United States until it’s safer.
On the same day that the French researcher was denied U.S. entry, Baptiste published a letter urging French research institutions to welcome American scientists questioning their future. Some French universities have already started to do so.
—Kimberly M. S. Cartier (@astrokimcartier.bsky.social), Staff Writer
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