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

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.