GM's legal tactics in the crosshairs of Congress

For over a decade, the General Motors legal department quietly worked to contain the damage of defective ignition switches.

On Thursday on Capitol Hill the man who has overseen GM's legal team will be asked to explain why his staff settled cases involving a faulty part but never brought the issue to senior management for further investigation.

Michael Millikin, GM's General Counsel, will be on the hot seat before the Senate Subcommittee on Consumer Protection following up on how the automaker handled lawsuits involving the faulty part.

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In many cases, GM reached settlements that were sealed.

Keeping settlements sealed is a common tactic in corporate America, but with GM failing to disclose defective ignition switches, many are asking if the automaker's legal team contributed to a cover up.

"I intend to ask why these settlements are being kept secret and demand GM make them pubic," said Senator Richard Blumenthal of Connecticut.

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That question is one of many that will be asked of Millikin.

Whether or not he gives detailed answers is open for debate. With GM facing a slew of lawsuits, Millikin may decline to give specifics.

General Motors CEO Mary Barra
Getty Images
General Motors CEO Mary Barra

In his prepared remarks before he is questioned, Millikin will tell Senators he didn't know about the ignition switch issue until February, shortly before GM announced a recall of 1.3 million vehicles.

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"Had I learned about it earlier, I would have taken action earlier," Millikin will testify.

Legal practice review

Millikin will also tell the Senate Subcommittee that GM has hired an outside law firm to review the automaker's legal practices.

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One practice that has changed is Millikin now approving the settlement of any case involving a fatality or serious injury.

That was not how GM handled ignition switch cases.

Instead, the automaker's legal staff would approve settlements of cases without alerting upper management inside the company.

Millikin will point out that several of the 15 employees GM dismissed for their roles involving the ignition switch crisis were lawyers in the company.

"We had lawyers at GM who didn't do their job, didn't do what was expected of them," Millikin will testify.

That may be the case.

Still, Thursday on Capitol Hill, Senators will question why Millikin didn't know more, didn't do more as case after case was brought against the automaker.

By CNBC's Phil LeBeau.

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