Two U.S. senators on Thursday urged the National Highway Traffic Safety Administration (NHTSA) to reconsider its decision to tell automakers not to comply with a recently effective Massachusetts state “right to repair” law designed to allow customers access to vehicle data.

Massachusetts voters approved a 2020 ballot initiative to allow independent repair shops to access diagnostic data that newer cars can send directly to dealers and manufacturers to allow consumers to seek repairs outside dealerships.

NHTSA told 22 major automakers in a letter on Tuesday they must comply with a federal vehicle safety law and not with the Massachusetts law, which came into effect on June 1. It warned that a malicious actor “could utilize such open access to remotely command vehicles to operate dangerously, including attacking multiple vehicles concurrently.”

Senators Elizabeth Warren and Ed Markey, both Democrats of Massachusetts, said in a letter to NHTSA and the U.S. Department of Transportation that the agency’s decision “to give auto manufacturers a green light to ignore state law appears to favor Big Auto.”

They added the decision will “undermine the will of Massachusetts voters and the Biden Administration’s competition policy, and raise questions about both the decision process and the substance of the decision by NHTSA’s leadership.”

They sought details on any meetings NHTSA held with auto industry lobbyists and asked if it conducted tests about the impact of the law.

Neither USDOT nor NHTSA issued an immediate comment.

NHTSA said in its letter to General Motors Co., Tesla Inc., Ford Motor Co., Toyota Motor Corp., Rivian Automotive Inc., Volkswagen AG and others that open access “allows for manipulation of systems on a vehicle, including safety-critical functions such as steering, acceleration, or braking.”

The Alliance for Automotive Innovation, a trade group representing major automakers, has sued to block the law and unsuccessfully asked a federal judge to temporarily block its enforcement. The group did not immediately respond to a request for comment on Thursday.

(Reporting by David Shepardson; Editing by Leslie Adler and Richard Chang)