Anton Valukas, right, and General Motors CEO Mary Barra testified before a House Subcommittee on Oversight and Investigations on Wednesday.

"We're hearing there may be up to 100 deaths linked to this." – Rep. Diana DeGette

A member of the US House of Representatives said Wednesday there may be as many as 100 deaths linked to General Motors' decade-long failure to recall millions of defective cars.

Rep. Diana DeGette (D-Colorado) referenced the figure during her questioning of GM CEO Mary Barra and former US Attorney Anton Valukas in a hearing of the House Subcommittee on Oversight and Investigations, which has been probing the ignition-switch defect.

"We're hearing there may be up to 100 deaths linked to this," DeGette said during her remarks.

The number of deaths tied to the faulty ignition switches has been an elusive figure thus far amid several investigations. General Motors has acknowledged at least 13 deaths and 54 crashes that occurred when the switches inadvertently moved out of the "run" position and turned off engines, airbags and other electrical systems, like power steering.

But several families of people who died in accidents are angry that GM has not counted their family members as part of its number, and an earlier Reuters analysis found that as many as 74 people may have died in accidents related to the problem.

DeGette did not elaborate on her comments in her official remarks, but a spokesperson from her office said "safety advocates and others continue to look at crashes that contributed to fatalities beyond the 13 GM has acknowledged. ... While no counts are settled yet, we have heard numbers like the 100 my boss referenced from people who are closely tracking this."

Barra did not detail how GM might determine the eligibility requirements for the compensation fund.

Although the company knew about the defective switches for more than a decade, GM didn't recall any of the Chevrolet Cobalts, Saturn Ions or Pontiac G5s affected until February of this year. So far, GM has recalled 2.6 million cars related to that problem.

More broadly, General Motors has had to revamp the way it treats safety concerns within the company. In the wake of the fiasco, General Motors has issued 44 separate recalls in 2014 that cover more than 20 million vehicles worldwide – more than the number sold by GM the past five years combined.

In her testimony, Barra affirmed GM's 13 acknowledged deaths. Rep. Pete Olson (R-Texas) noted there were pictures of 15 victims in the back of the gallery and asked her to explain the discrepancy. Barra instead relayed details of a victim-compensation program that will be independently administered by Kenneth Feinberg, but as in previous appearances, the details of which remained unclear Wednesday.

Sidestepping a question about the deaths not acknowledged by GM, Barra said that all potential victims were "eligible to apply" for funds from the compensation fund, but she did not detail how GM might determine the eligibility requirements. She said that was a question that Feinberg would answer by the end of the month, and that he would begin accepting claims by August 1.

Rep. Morgan Griffith (R-Virginia) asked Barra, if she truly wants to make sure all victims are fairly compensated, why GM's lawyers are continuing to seek shield from liability provided by the company's 2009 bankruptcy filing.

"You feel it's the right thing for GM to continue to seek the shield of bankruptcy and not deal with these cases? And have Feinberg be the only solution," Griffith said. Barra noted that participation in Feinberg's program is voluntary and that, for those who don't participate, "people have the same rights they do today," she said.

In perhaps the most heated exchange of the testimony, Griffith responded, "But you're trying to block those rights, by not instructing your lawyers to back off. ... If GM truly wants to compensate victims fully and fairly, stop asking the bankruptcy court for protection."

"If GM truly wants to compensate victims fully and fairly, stop asking the bankruptcy court for protection." – Rep. Morgan Griffith

Former US Attorney Anton Valukas, who authored the 325-page internal report on the GM response to the ignition-switch problem, sat beside Barra at the witness table and also took questions from lawmakers Wednesday. Among the biggest revelations: He said that Delphi, the supplier that made the ignition switches for GM, had been largely unresponsive to his requests for information. In multiple instances, he said Delphi either could not locate documents he asked for or did not produce them. In another instance, he said that Delphi did not grant him access to employees he wanted to interview.

In regard to the defective ignition switch, Valukas testified that "Delphi certainly knew this part was being approved."

Delphi has not yet responded to a request for comment.

Released two weeks ago, Valukas' internal report found no evidence of a company-wide cover-up and largely absolved GM's senior leadership of blame in the delayed ignition-switch recall. That explanation hasn't sat well with safety advocates who have called it a whitewash, and it didn't sit well with several skeptical members of the Congressional committee.

"In many ways, the facts surrounding what finally resulted in the GM recall are far more troubling," Rep. Tim Murphy (R-Pennsylvania) said.

Noting that the company had known about the defective switches for at least a decade, met with members of the National Highway Traffic Safety Administration in 2007 to discuss problems with Chevy Cobalts and then learned in a deposition in April 2013 that the ignition switch had been replaced by an engineer without changing a part number, Rep. Phil Gingrey (R-Georgia) said, "that smacks of a big cover-up to me."