An internal investigation led by former federal prosecutor Anton Valukas — paid for by GM — showed that even as GM lawyers recommended the settlement of similar cases involving crashes where front air bags failed to deploy in Chevrolet Cobalts and Saturn Ions, they didn't alert higher-ups, including Millikin, to a potential safety issue. Lawmakers may also question Valukas about the report's conclusion that a lone engineer, Ray DeGiorgio, was able to approve the use of a switch that didn't meet company specifications, and years later, to order a change to the switch without any senior executives at GM being aware. Sen.