A new lawsuit has been filed that accuses General Motors of fraud and concealing evidence related to the faulty ignition switches that have been linked to at least 13 deaths.
It is believed to be the first suit filed since documents surfaced showing a GM engineer allegedly signed off on changing a part in the switches but not changing the part number, which would have alerted others at GM or Delphi, the switchmaker, that it had been altered.
"General Motors secretly changed this part, then lied about it," attorney Lance Cooper said in a conference call. "We want to know how many inside General Motors knew about this lie."
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Cooper filed the lawsuit on behalf of Ken and Beth Melton. The couple's daughter, Brooke, died in 2010 when her 2005 Chevy Cobalt collided with another car and went off the road in Cobb County, Georgia. The Meltons sued GM over that crash and settled for an undisclosed sum last year.
Now, the family is accusing the automaker of fraud.
In a written response, GM said, "General Motors has taken responsibility for its actions and will keep doing so. GM has also acknowledged that it has civic and legal obligations relating to injuries that may relate to recalled vehicles, and it has retained Kenneth Feinberg to advise the company what options may be available to deal with those obligations."
The new lawsuit revolves around the deposition of GM engineer Ray DeGiorgio. Cooper deposed DeGiorgio during the Meltons' first lawsuit and asked him about changing a part of the ignition switch. Under oath, DeGiorgio said he did not authorize any changes to the switch.
However, documents turned over to the National Highway Traffic Safety Administration and Congress showed DeGiorgio signed off on changing a key piece of the switch. Because of a defect, the switches could slip into accessory mode, leaving the vehicle with no electronics, power steering or airbags.
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Senators on Capitol Hill showed the document to GM CEO Mary Barra when she testified before Congress in early April. At the time, Sen. Claire McCaskill (D-Mo.) wanted to know why Barra and General Motors had not disciplined DeGiorgio and another GM engineer, Gary Altman, who worked on the ignition switches.
Shortly after the hearings, both engineers were put on paid leave.
"The Meltons would not have settled their case if they had known of the perjury and concealment of critical evidence," Cooper said. "It is now apparent that GM's plan was to resolve the Meltons' claims before disclosing the Cobalt ignition switch design changes."
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General Motors has now recalled almost 2.6 million cars that may have faulty ignition switches.
Cooper said he hopes to once again depose all of the General Motors executives who he questioned during the Meltons' first lawsuit.
"We do not have any plans to talk to Ms. Barra at this time," Cooper said. "But eventually we would like to depose her as well."
Barra has said from the beginning of the crisis that she had no knowledge of the faulty ignition switch before GM executives alerted her late last year of plans to issue a massive recall. Since then, no evidence or documents have turned up that link Barra to the defective switches.
—By CNBC's Phil LeBeau.
Questions? Comments? BehindTheWheel@cnbc.com.