Leah B. Foley United States Attorney for the District of Massachusetts | Department of Justice
A Brazilian national living in Marlborough without legal status pleaded guilty in federal court in Boston to dealing firearms without a license. Guilherme Fernandes-Tavares, 32, entered his plea before U.S. Senior District Court Judge Patti B. Saris, who set sentencing for February 26, 2026.
Fernandes-Tavares was charged by criminal complaint in March 2025 and later indicted by a federal grand jury in July 2025. According to court documents, between December 2023 and May 2024, he sold 11 firearms and ammunition over the course of 10 separate transactions and offered additional weapons for sale.
Authorities stated that the firearms included pistols, some of which were privately manufactured without serial numbers. One firearm had its serial number removed, and another was sold with a magazine capable of holding 28 rounds. Law enforcement also intercepted a package sent from Florida to Fernandes-Tavares containing an additional firearm.
The charge carries a maximum penalty of five years in prison, three years of supervised release, and a fine up to $250,000. Sentencing will be determined according to federal guidelines and statutes.
United States Attorney Leah B. Foley said: "Valuable assistance was provided by the U.S. Postal Inspection Service; Massachusetts State Police; and the Westborough Police Department." The investigation involved multiple agencies including the Bureau of Alcohol, Tobacco, Firearms & Explosives; Homeland Security Investigations; and U.S. Immigration and Customs Enforcement’s Enforcement and Removal Operations. Assistant U.S. Attorney John J. Reynolds III is prosecuting the case.
