Federal prosecutors on Tuesday asked to drop the smuggling charges against Kseniia Petrova, a Russian-born researcher at Harvard accused of bringing Frog embryos into the United States without declaring them. Petrova has argued that she was unfairly targeted after her arrest in February 2025, amid the Trump administration’s immigration crackdown.
A federal judge in Massachusetts granted Petrova’s lawyers a broad discovery request in April, which would have required the government to provide evidence about similar cases. In its request to dismiss the charges, the government said it could not provide that material without revealing non-public information about U.S. Customs and Border Protection operations and investigative techniques.
Prosecutors said the move was not prompted by Petrova’s allegations of government overreach, which they described as “meritless.” Assistant U.S. attorney David Holcomb wrote that continued litigation would consume significant time and resources, outweighing the public interest in resolving the case.
Petrova’s lawyer, William Fick, said the case should never have been brought and welcomed the decision. He said the samples were inert, non-living and non-toxic, and that Petrova had been seeking to support medical research into aging.
Petrova was detained at Boston’s Logan International Airport in February 2025 after customs officials found undeclared biological samples in her luggage. She had been vacationing in France when her Harvard supervisor asked her to bring samples back from a French laboratory. Her lawyer said that failing to declare the items would ordinarily have been a relatively minor infraction. Petrova’s visa was canceled, and she was taken into custody before being released on bail four months later.
In a separate immigration case in April, a district court judge in Vermont ruled that the cancellation of Petrova’s visa was unlawful, describing it as arbitrary and not carried out in accordance with required procedures.
Sources: The New York Times Science.