A judge has ruled that the National Marine Fisheries Service violated federal law when it allowed New England fishermen to carry uncaught groundfish allocation into the following year.

The service made the adjustment as part of a group of changes to New England’s Multispecies Fishery Management Plan in 2013. Judge James E. Boasberg of U.S. District Court for the District of Columbia ruled April 4 the carryover provision increases likelihood that “environmental harm, in the form of excessive fishing” would take place.

Boston-based Conservation Law Foundation brought the lawsuit. The group contended allowing carryover would jeopardize groundfish populations.

A spokeswoman for the National Marine Fisheries Service said the agency is determining how to respond to the ruling. The agency is part of the National Oceanic and Atmospheric Administration.