EDITORIAL MORE COPS, LESS CRIME RECENT EXPERIENCE CONFIRMS COMMON SENSE.

THE recent drop in crime in the northeast San Fernando Valley - following the transfer of more than 20 cops into the area - reaffirms an axiom of modern policing:

Where there are officers, there will be less crime.

That holds true for all of Los Angeles - not just the Northeast Valley.

Within the past year, crime had gone up 8 percent throughout Los Angeles and 10 percent in the Valley. Thanks to the LAPD's doubling its efforts and a recent cold-weather spell, the Northeast Valley now shows signs of reversing that trend.

But to achieve the crime drop-off in the Northeast Valley, the Los Angeles Police Department has had to bring in scarce resources from elsewhere. The result is that the welcomed crime drop in one part of the city will likely be followed by commensurate increases in others.

That leads to a second, corollary axiom of modern policing:

Where there are fewer officers, there will be more crime.

That was clear in the Northeast Valley last weekend. When cops saturated the area Friday night and Saturday morning, gang violence was down. But by Sunday night, the thugs were at it again, attacking one man in Sylmar, then shooting five people and wounding a 14-year-old boy in San Fernando.

The problem is that the LAPD lacks the personnel to put enough cops in all places at all times. With the recent flop of a nationwide recruiting effort, it now finds itself 1,000 officers short - and heading backward to where it was when Richard Riordan was elected mayor with the promise to add 3,000 officers, a promise that was barely half fulfilled at the peak.

And as the department has become consumed with policing itself, its ability to police the streets has suffered all the more. In the past year, the number of investigated complaints against LAPD officers has doubled. That puts more cops behind desks and shuffling papers, instead of on the streets and walking the beat.

With the impending consent decree slated to cost the city some $50 million a year, it's likely that the number of active LAPD officers will only continue to decrease in the years ahead.

That leaves the department desperate to overachieve, stretching itself thin and occasionally saturating high-crime areas.

In the short term, that strategy can pay off. But citywide and over time, when there aren't enough cops, gang members will run the town.

A return to the high crime rates of a decade ago is likely, unless L.A. pays as much attention to beefing up its police force as it does to scrutinizing its every alleged transgression.

The evidence couldn't be more clear: L.A. needs more cops.

Just ask the residents of the Northeast Valley.