'It was a cover-up': New allegations against GM

Two lawyers at the heart of the case said a new round of drama will soon take place.

Just when it seemed as if the major fireworks surrounding 2.6 million defective—and in some cases deadly—General Motors (GM) ignition switches were starting to fade, two lawyers at the heart of the case said a new round of drama will soon take place.

Lance Cooper and Jere Beasley, two attorneys who have handled lawsuits involving the defective ignition switches, say a fresh round of litigation has uncovered proof that GM actively tried to cover up the problem switches.

If the allegations are true, they would run counter to the conclusion of General Motors' internal investigation, which blamed incompetence as the primary reason the automaker approved the use of faulty ignition switches, and then was slow to recall them once it learned of accidents.

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"We believe the documents show, and the testimony that will come out that this wasn't incompetence, it was a cover-up," Cooper said.

General Motors did not immediately respond to CNBC's request for comment on the allegations.

In the conference call with reporters on Monday, Cooper said the evidence to support his allegation will come out when the first class action lawsuit surrounding the defective switches takes place in January.

Attorneys are already in the midst of discovery and are exchanging documents. Later this year, Cooper said he expects former and current GM engineers and executives to be deposed about what they knew regarding the faulty switches.

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"Beginning in May and running throughout the end of the year, depositions of all important General Motors witnesses will be taken, including high-level executives," he said.

It's unclear if GM CEO Mary Barra will be deposed as part of the class action case. Barra took over as chief executive shortly before the automaker announced the first round of recalls involving defective switches. She has maintained throughout the controversy that she did not know about the faulty parts until shortly before the first recall was announced in February 2014.

The GM internal investigation also concluded Barra did not know about accidents related to defective ignition switches prior to becoming CEO that January.

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In June, during an interview on NBC's "TODAY" show, Barra said, "I really don't think it was a cover-up."

The new round of allegations comes as the GM ignition switch compensation fund announced that it has determined 67 people were killed in accidents involving defective GM vehicles—a substantial increase from the 13 GM initially reported.

The compensation fund, which is run by attorney Ken Feinberg, has approved claims filed by 113 people injured in faulty GM vehicles. Nearly 1,500 claims are still under review.

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