If he was deemed to be drunk, that's an aggravating circumstance to his crimes and will add years to his penalty.
Sad thing is in the US there really is often not a lot of punishment for killing with your car when sober. There are outlier cases, but generally speaking the US doesn't have a history of punishing it severely depending on what state you are in. Some aren't even a felony.
As an example
Many states recognize different degrees of vehicular manslaughter. Statutes typically authorize more severe punishment for vehicular manslaughter convictions involving drunk or drugged drivers, as opposed to convictions based on non-DUI traffic offenses. For example, in Georgia, a driver who causes a death while intoxicated can be charged with first-degree vehicular homicide, a felony carrying up to fifteen years in prison. But a driver who causes a death while committing a moving traffic offense (such as failure to maintain lane position), is guilty of second-degree vehicular homicide, a misdemeanor carrying a maximum of a year in jail.
