Report: GM Internal Probe Focusing on Legal Department

General Motors Co.'s own investigation into its laggardly response to a fatal ignition switch defect suggests the company's legal staff attempted to cloak GM's effort to fix the problem from the families of crash victims and others, according to The New York Times.

GM agreed to five confidential settlements involving the switches to avoid publicizing the issue, according to the newspaper. One of them was an unexpected agreement last September to settle a lawsuit filed by the family of Brooke Melton, who died in Georgia when her Chevrolet Cobalt crashed in 2010.

The Melton case prompted GM to revive an internal review of the ignition switch problem. That's when the company discovered the switch had been quietly upgraded in 2006, even though such a change was denied by the engineer in charge of the component when he was deposed in April 2013 for the Melton lawsuit.

The Times says GM's legal department appears to have delayed for at least three months a response to a request by the company's investigators for documentation about the altered switch.

Separately, the National Highway Traffic Safety Administration sent a letter to GM last July complaining about the company's slow response to several safety issues. The letter was circulated to several high-level GM executives. But the Times says the company didn't act on the ignition switch defect for another six months.

Internal e-mails, documents and interviews show high-ranking executives have responded "with increasing urgency" only in the past 12 months as lawsuits threatened to reveal the scandal. GM announced in February it would recall 2.6 million cars to replace their ignition switches. The company hopes to fix at least half the affected cars by October.