Five days ago, when we told you the National Academy of Sciences was backing the National Highway Traffic Safety Administration’s findings into unintended acceleration issues concerning Toyota Priuses, we speculated it wouldn’t be the last we’d hear on the matter.

Now an American safety group has sued the U.S. Department of Transportation under the Freedom of Information Act in order to gain access to documents which it says will back claims that the official NHTSA investigation was flawed.

Further more, Massachusetts-based Safety Research & Strategies Inc. -- an 8-year old company focused on highlighting and rectifying vehicle safety concerns as well as offering automotive safety litigation expertise to consumers -- makes the serious claim that NHTSA investigators massaged data to prove that elecronics faults were not the cause of  unintended acceleration incidents. 

“This is all about transparency,” said co-founder of Safety Research Sean Kane. “This is an agency that selectively releases data that fits its narrative that electronics are not at fault in sudden acceleration.”

According to Kane, the firm is in possession of a sworn statement from a Government employee whose personal 2003 Toyota Prius accelerated without warning multiple times on a 200-mile trip in May last year.

2008 Toyota Prius

2008 Toyota Prius

Kane claims when NHTSA investigators arrived the home of Mr. McClelland -- an engineer and director of the Office of Electric Reliability at the Federal Energy Regulatory Commission -- to investigate the issue, the NHTSA employees witnessed the strange behavior for themselves.

“They generally seemed excited,” McClelland said. “They said they hadn’t seen a vehicle display this type of behavior before, capturing the information in real time, and they said this could be an important vehicle for the sudden accelerations and it might help put some of the pieces together.”

But according to The New York Times, McClelland was told months later that the car’s age and high mileage were the probable cause of the symptoms, not a fault in the vehicle software or design.

The original NHTSA investigation began in 2009 after an horrendous, highly publicized event in which a Lexus hybrid crashed after speeding along a California highway, apparently out of control. All four occupants were killed. 

After that event, other Lexus and Toyota Prius drivers stepped forward, claiming that their cars had also started to accelerate without warning. Some of the cases appeared genuine, while others were less plausible.

At the time, Toyota investigated the incidents and concluded that the problems were most likely caused by a sticky throttle, the fitting of inappropriate floormats, and user error. 

2004 Toyota Prius accelerator pedal after being shortened as part of sudden-acceleration recall

2004 Toyota Prius accelerator pedal after being shortened as part of sudden-acceleration recall

As a consequence, it launched an official recall program to fix the first two issues, and cautioned drivers about the later. 

But when Apple co-founder Steve Wozniak reported that his 2010 Toyota Prius was also experiencing an acceleration problem which he said was a software glitch, all eyes turned to the millions of lines of code that the Toyota Prius needs to operate. 

Despite Toyota later explaining that Wozniak’s problems were down to the Prius’ wacky adaptive cruise control, electronic software and hardware failure became a key part of the NHTSA’s official investigation.

The latest twist in the story of unintended acceleration in Toyota Priuses will most likely unfold over the coming months. But with the NHTSA already under fire for other safety investigations, we think the case isn't closed just yet.


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