As reported by engadget,
For Tesla, today’s decision will come as vindication. When the news of the petition first came out, the company said it was “completely false,” and went on to claim it was a ploy by a “short-seller” to make some money off of its misfortune. At the time, Tesla claimed it had already designed its cars to avoid any potential issues with unintended acceleration. Each one of the company’s cars comes with two pedal position sensors that will automatically shut off motor torque if they detect “any error.” That failsafe is complimented by the company’s Autopilot system, which it designed to catch any pedal abuse.
The person who had petitioned the NHTSA to look into the incidents had asked that the agency recall all Model S, X and 3 vehicles if it found any safety issues. As such, Tesla has avoided a potentially devastating recall, but that’s not to say the automaker is in the clear for good. The NHTSA said it could revisit the issue in the future (or any other problem, for that matter) if new information comes to light.