Senators on Wednesday accused General Motors of having a "culture of cover-up" that led to the deaths of 13 people.
Often taking a prosecutorial tone with GM CEO Mary Barra, Sen. Claire McCaskillClaire McCaskillJuan Williams: Senate GOP begins to push Trump away Dem senator: I may face 2018 primary from Tea Party-esque progressives Dems ask for hearings on Russian attempts to attack election infrastructure MORE (D-Mo.), chairwoman of the Senate subpanel looking into the recall of more than 1 million GM vehicles due to a dangerous ignition switch flaw, said the automaker had a "culture of cover-up that allowed an engineer to lie under oath repeatedly."
"We don't know how many people crashed because of this cover-up," McCaskill said. "We do know that many died."
But members on the Senate's Commerce, Science and Transportation subcommittee on consumer protection and product safety appeared to be less accepting of the GM chief's attempts to separate herself from decisions that were made before she assumed the helm of the company this year.
"You're new at your job, but you've been GM for how many years?" Sen. Barbara BoxerBarbara BoxerCarly Fiorina 'certainly looking at' Virginia Senate run Top Obama adviser signs with Hollywood talent agency: report Democrats vie for chance to take on Trump as California governor MORE (D-Calif.) asked Barra, a second-generation General Motors employee who recently became the first woman to be placed in charge of a major U.S. automaker. She has worked for the company for 33 years.
"You're a really important person to this company," Boxer continued after reading Barra's lengthy GM resume. "Something is very strange that such a top employee would know nothing."
At issue is GM's recall of more than 1.6 million vehicles that were found to have defective ignition switches that caused the cars to shut off abruptly or have their airbags disabled. The Senate hearing Wednesday was attended by families of the 13 car crash victims who died in accidents that have been linked to the faulty GM parts.
Lawmakers in both chambers and parties have accused GM and the National Highway Traffic Safety Administration (NHTSA) of taking too long to notify drivers of the problems with cars that were, in some cases, more than a decade old.
As she did in a contentious House hearing on Tuesday, Barra sought Wednesday to drawn a distinction between a "new GM" that is operating under her leadership and prior regimes at the automaker.
"More than a decade ago, GM embarked on a small car program," the GM chief said. "Sitting here today, I cannot tell you why it took years for a safety defect to be announced in that program, but I can tell you that we will find out."
Members of the Senate subcommittee did not appear to be swayed by Barra's arguments.
"Ms. Barra, I really hate to say this, but if this is the new GM, it is sorely lacking in leadership," Boxer said.
Boxer added that she was disappointed in Barra's lack of direct answers.
"As a woman to woman, I am very disappointed, because the culture that you are representing here today is a culture of the status quo," Boxer said in an exasperated tone.
Earlier in Wednesday's hearing, Boxer mocked Barra's attempts to separate herself from earlier GM decisions.
"What about 2005? Is that the new GM or the old GM," Boxer asked. "Yesterday, I did some things that I'm accountable for."
Barra promised again to act quickly to rectify the recall situation.
"As soon as I learned about the problem, we acted without hesitation," she said. "We told the world we had a problem that needed to be fixed. We did so because whatever mistakes were made in the past, we will not shirk from our responsibilities now and in the future."
The NHTSA is also under fire for its handling of the GM recalls.
Lawmakers accused the agency Thursday of failing to notice the trend of accidents involving GM's faulty ignition switch for several years before the recall was issued in February.
”I could go on my iPad right now and Google 'lawsuits against General Motors,' and pull up hundreds of them, I'm sure, in fairly quick order," McCaskill said of news reports about accidents that were linked to the defective GM parts.
Acting NHTSA Administrator David Friedman placed blame on GM, alleging the company provided inaccurate information to his agency.
”Our ability to find defects also requires automakers to act in good faith and provide information on time," he said. "General Motors has now provided new information definitively linking air bag nondeployment to faulty ignition switches, identifying a part change, and indicating potentially critical supplier conversations on air bags. Had this information been available earlier, it would have likely changed NHTSA's approach to this issue.”
This story was last updated at 4:32 p.m.