For many years, General Motors knowingly installed ignition switches that failed to meet specifications in Chevy Cobalts and other small cars. Since then, at least 13 people have died in accidents linked to defective switches GM could have replaced for $2. GM has admitted that officials knew of defective ignition switches for almost 10 years before undertaking a massive recall this year. Now, there's a criminal probe and Congress is asking, 'what did GM executives — and federal regulators -- know and when did they know it?' Can Mary Barra, the company's new CEO, persuade Capitol Hill and millions of customers that GM has cleaned up its act since the federal bailout?