More than 200 incidents involving Teslas unexpectedly accelerating and crashing were the fault of drivers confusing their brake and accelerator pedals, not a defect with the electric vehicles, the federal car safety agency said Friday.

The National Highway Traffic Safety Administration opened the investigation a year ago, acting on a petition filed by an independent investor. Complaints received by the agency from Tesla owners alleging so-called sudden unintended acceleration included accounts of the vehicles hitting a palm tree, a fire hydrant, walls and other cars. One of the complaints was accompanied by a photograph of a Tesla Model S that had shot through the back wall of a garage.

After completing its review, however, the agency concluded there was no indication that faulty parts or a bad design caused of the incidents.

“The evidence shows that SUA crashes in the petitioner’s complaints were caused by pedal misapplication,” the agency said in a statement. “NHTSA found no evidence of fault in the accelerator pedal assemblies, motor control systems, or brake systems that contributed to the cited incidents. NHTSA also found no evidence of a design factor contributing to increased likelihood of pedal misapplication.”

Electric vehicles are capable of rapid acceleration typically only seen in high-end gas-powered cars, which could help explain accounts of Teslas jumping off from almost a standstill.

“NHTSA reminds drivers that they are responsible for their vehicle’s safe operation and manufacturers are encouraged to take further steps to educate new consumers on safe vehicle functionality,” the agency said in its statement.

Brian Sparks, the investor who filed the petition, said the rates of complaints about sudden acceleration incidents in Teslas were “astonishingly high” compared with other kinds of vehicles but that he accepted the findings of the federal review.

“If NHTSA says there is no defect then I consider the matter settled,” Sparks said. “I appreciate NHTSA’s work.”

Sparks relied on a rarely used a process called a defect petition, which allows a member of the public to force NHTSA to begin a review. He supplied records of 232 complaints involving Tesla’s Model S and Model 3 sedans and the Model X SUV, and the agency identified another 14. But after reviewing the available data, NHTSA concluded that the incidents were caused by drivers not the vehicles themselves.

Tesla has had a contentious relationship with federal safety agencies in recent years as the company has grappled with the implications of advanced cruise control technologies it has been rolling out. Safety advocates have warned that the company has put technology into the hands of consumers who don’t properly understand it and incorrectly believe their cars are capable of safely driving themselves.

Those advocates also say that under the Trump administration, NHTSA has done too little to set rules for the use of the technologies by automakers.

Customers and stock market investors have stuck with the company. This week its chief executive Elon Musk appeared to have become the richest person in the world.