The assault against drunk driving received a state high court ruling in its favor last week, but that ruling isn't likely to result in great inroads toward getting intoxicated motorists off the highways.

Roving police patrols will remain as the most effective weapon and that is where the police emphasis must continue be.

The court ruling didn't take issue with such an assumption.

In last week's ruling, the state Supreme Court upheld the 2003 driving-under-the-influence conviction of a Pittsburgh man who was stopped by Pittsburgh police at a DUI roadblock and arrested in 2001. The motorist appealed, asserting that sobriety checkpoints should be declared unconstitutional if there is a more efficient way to enforce the state's DUI law.

The high court justices acknowledged that state Department of Transportation statistics reveal that the perentage of DUI arrests among drivers who are pulled over - 7.7 percent - is more than 10 times higher than the percentage arrested for DUI at checkpoints.

However, commendably, Justice Thomas Saylor wrote in the majority opinion that "this alone does not mean they (roadblocks) are ineffectual."

In upholding the constitutionality of the checkpoints, the court said, "Based on the record before us, we find that the trial court properly concluded that (the motorist who appealed) failed to show that DUI roadblocks are so ineffective that they must be declared constitutionally unreasonable."

The high court did reaffirm the need for careful planning and execution of the checkpoints to avoid conflicts with constitutional protections against unreasonable searches and seizures. That point is important amid the checkpoints-issue debate.

Contrary to what some people perceive, publicly advertised checkpoints do serve as a deterrent to drunken driving. The announcement about upcoming checkpoints is likely to encourage more use of designated drivers.

It's also true that some people who drink and drive, when they hear that checkpoints will be set up, merely opt to travel in areas less likely to be targeted for the checkpoints.

That's why, although checkpoints serve a good, legitimate purpose, roving patrols are still the best weapon for enforcing the law against drunk drivers. Those patrols target drivers who display signs of impairment - those drivers who, in many instances, pose the most danger to others and themselves.

Nevertheless, the high court's decision in the case in question is to be applauded.