RIGHTS OF LAW-ABIDING CITIZENS ARE UPHELD

In a ruling last week, the U.S. Supreme Court tried to distinguish between police roadblocks aimed at catching lawbreakers who are an immediate threat to society and other roadblocks likely to collar miscreants whose crimes, while serious, may not be a threat to other motorists.

The case had to do with roadblocks set up in 1998 by Indianapolis police who were trying to catch drug dealers in a high-crime neighborhood. Over a four-month period, police stopped 1,161 vehicles at random, making 104 arrests -- of which 55 were drug charges.

In the majority opinion for the 6-3 decision, Justice Sandra Day O'Connor said the benefit to the public must outweigh the inconvenience to motorists.

As the numbers from Indianapolis indicate, more than a thousand of the vehicles that were stopped in Indianapolis weren't involved in any crimes at all. Attorneys for two of those uncharged motorists sued to stop the practice, saying it was unfair to innocent motorists even though the net result produced 55 drug arrests.

But, O'Connor argued, this wasn't enough to give police free rein to use roadblocks to catch motorists who might be involved in any kind of crime, such as an expired driver's license. To be arrested for not having a driver's license under these circumstances, O'Connor said, violated the Fourth Amendment's protection against unreasonable search and seizure.

Meanwhile, the Supreme Court already has ruled that roadblocks to catch intoxicated drivers are OK. What's the difference? As the majority in the opinion held, drunk drivers are an immediate threat to themselves and the motoring public at large, and police are justified in using sobriety checkpoints to get drunks off the road.

In short, the court said there are limits on police activities that set out to catch one kind of lawbreaker but wind up in arrests for various other crimes -- or, in the case of most stopped motorists, no charges at all.

Chief Justice William Rehnquist and Justice Clarence Thomas dissented, joined in part by Justice Antonin Scalia. Rehnquist wrote that police roadblocks in high-crime neighborhoods are valuable public safety and crime-fighting tools.

The good news is the Supreme Court -- even one generally considered to be conservative -- has once again exercised great caution in the area of the rights of law-abiding citizens who happen to be on a street where police are randomly stopping and searching vehicles.

The not-so-good news is that police departments need every tool possible to find serious offenders and get them off the streets.