Montgomery County Police Officer Noah Leotta, who died after being struck by a suspected drunk driver in December. (Courtesy of Noah Leotta’s family)

OVER THE better part of a decade, Democrats who run Maryland’s House of Delegates have gradually been pushed to get tougher with drunk drivers, with plenty of griping along the way. In thrall to the alcohol lobby and to trial lawyers — whose numbers include Joseph F. Vallario Jr. (D-Prince George’s), the powerful chairman of the House Judiciary Committee — they have sought to maintain ways to go easy on motorists who are menaces to public safety.

This year, thanks to Officer Noah Leotta, their foot-dragging may finally succumb to the force of public opinion.

Leotta was the young Montgomery County police officer killed by a suspected drunk driver in December while on patrol along Rockville Pike. He was on the lookout for intoxicated drivers when one struck him on the side of the road, where he had pulled over another car. That tragedy changed the political equation in Annapolis. For the first time in years, Mr. Vallario could not slap down efforts by reform-minded lawmakers and advocates to tighten Maryland’s squishy laws.

Still, real reform is in the details — and the details of Maryland’s drunken-driving laws may be the most mind-bendingly convoluted in the nation. That appears to be by design, constituting a boon to the fraternity of defense lawyers who can solicit business by plausibly asserting that they alone can unravel the fine points in state statutes.

As things currently stand in Annapolis, two versions of a bill to toughen drunken-driving penalties have passed the legislature — one with real teeth, which has passed the state Senate, and a flimsier one, which, vetted by Mr. Vallario, emerged from the House. Lawmakers should opt for the stronger Senate bill.

Each of the bills is an improvement on current law, which doesn’t crack down on most intoxicated drivers on their first arrest unless they are falling-down drunk. However, the House version of the bill contains loopholes that would enable many drunk drivers to avoid having a mandatory Breathalyzer installed on their car’s dashboard — a device known as an interlock that prevents a car’s engine from starting if the motorist is intoxicated.

Under the Senate version, the interlock would be automatically installed in the car of any drunk motorist for 90 days upon arrest. And the clock would restart in the event the driver tried to operate his car while drunk at any point in the 90-day period. By contrast, the House bill would allow drunk drivers to opt out of an interlock by having their license suspended; many drivers with suspended licenses keep driving.

The two bills also differ on drivers who refuse to take a police Breathalyzer upon arrest. Under the Senate version, refusal would result in an interlock being automatically installed for 270 days. In the House version, drivers might again opt for a suspended license, and again ignore the sanction by continuing to drive.

Interlock devices are highly effective, allowing offenders to continue living a normal life if they can prove, by blowing into a tube affixed to their dashboards, that they are sober. They save lives. Maryland lawmakers have resisted such effective measures long enough, and at an unacceptably high price. It’s time for a no-nonsense approach.