California is one step closer to implementing Senate Bill 1046, which would require all drunken driving offenders to have ignition interlock devices installed in their vehicles.

The bill unanimously passed in the Senate and is now being considered in the Assembly. But it fails to address the core issue – the hard-core drunken drivers responsible for most alcohol-related fatalities. The bill also places a significant financial burden on the state, which will have to monitor and enforce compliance on a much broader scale.

Now, ignition interlocks are only required in four California counties as part of a pilot program: Alameda, Los Angeles, Sacramento and Tulare. A convicted drunken driver in these counties is required to have an ignition interlock, which prevents a vehicle from starting when a breathalyzer test detects alcohol.

Yet California’s Department of Motor Vehicles concluded that the pilot program “did not reduce drunken driving in general” and found no indication that it reduced the number of first-time and repeat DUI offenders.

Expanding the program statewide would cost the state millions of dollars without distinguishing between first-time offenders and hard-core drunken drivers who are responsible for the carnage in California. Roughly 70 percent of alcohol-related traffic fatalities are caused by drunken drivers with blood-alcohol levels nearly twice the legal limit or higher.

That’s why California should focus on guaranteeing high blood-alcohol and repeat offenders are complying with interlock laws. Research shows that fewer than 30 percent of offenders ordered to install interlocks actually do it, meaning states typically don’t have the resources to ensure compliance.

Shouldn’t we achieve a high rate of compliance among the most dangerous offenders before applying a broad mandate to those one sip over the legal limit?

A 120-pound woman can reach the 0.08 blood-alcohol limit after two 6-ounce glasses of wine over a two-hour period. Under SB 1046, if she were pulled over and convicted, she would automatically be punished with an ignition interlock for behavior that, according to numerous studies, is equivalent to driving while talking on a hands-free cellphone.

Mandating ignition interlocks for all DUI offenders is a one-size-fits-all approach that would eliminate a judge’s discretion.

What if we applied the same logic to speeding? Speeding is a major cause of fatalities on the highway, yet we don’t punish someone going 5 mph over the speed limit the same way as someone caught driving 30 mph over the limit.

Drunken driving is a serious problem that should be addressed with serious solutions. Unfortunately, SB 1046 is a feel-good, but ultimately unenforceable, measure.

The state Assembly has the opportunity to make Californians safer by demanding a more targeted approach to fighting drunken driving.