Public Citizen says the action by the National Highway Traffic Safety Administration puts consumers at risk, the Detroit Free Press said.
The NHTSA had considered requiring automakers to inform dealers about a safety defect within five days of notifying the government but decided against it.
"It is truly appalling that in not making consumers and dealers aware of defects as quickly as possible, NHTSA has weakened its own authority to protect the public," said Public Citizen President Joan Claybrook, who led the agency during the Carter administration.
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