FBI REPORTS 3% DIP IN U.S. CRIME.

Byline: Fox Butterfield The New York Times

Serious and violent crime dropped in the first half of last year, continuing a pattern that began five years ago, according to preliminary statistics to be released today by the FBI. The five-year decline is the longest in 25 years.

The figures, based on information reported to the FBI by local police departments, showed that the national crime rate decreased 3 percent in the first six months of 1996, led by a 7 percent drop in murders.

The news was greeted with applause by experts, many of whom have been reluctant until now to believe that the drop in crime figures was more than a short-term statistical aberration. But both the length of the decline and the fact that the biggest drop came in homicides, the most serious crime, appeared particularly significant to the specialists.

``I have been a skeptic,'' said Franklin Zimring, a leading criminologist and director of the Earl Warren Legal Institute at the University of California, Berkeley. ``But now, because of the length of the decline, its magnitude and the number of places it is occurring, I think I am experiencing a foxhole conversion.''

Alfred Blumstein, a professor of criminology at Carnegie Mellon University, said the causes of the decline in the crime rate were complex and hard to calculate in isolation. Some of the decrease, he said, could be attributed to more police officers on the streets and to the Brady law, which mandates a five-day waiting period for handgun purchases.

But, Blumstein said, ``I suspect it also has to do with the revised, more aggressive tactics'' being used by the police in a number of large cities, where police officers have made concentrated efforts to get handguns off the streets and to take them away from young people.

In fact, the figures to be released today show that the U.S. cities with populations of more than 1 million recorded the largest decline in overall crime - 6 percent in the six months.

Cities with populations of 500,000 to just under 1 million had no change in their crime rates, while smaller cities showed declines of 1 percent to 4 percent. Rural counties recorded a 3 percent drop and suburban law-enforcement agencies reported a 1 percent decrease.

Blumstein said that this appeared to continue a trend from 1995, when only three large cities - New York, Chicago and Detroit - accounted for 32 percent of the nation's drop in homicides.

The biggest cities tend to be ``more sophisticated and pick up on new police tactics more quickly,'' Blumstein said. And they also have the resources to move faster with new policing strategies.

It is becoming clear, Blumstein added, that William Bratton, the former New York City police commissioner who pioneered the city's tough new police efforts, has had a large influence on other police departments around the country. ``One of the things Bill Bratton did is capture a lot of police departments' attention,'' Blumstein said. ``After watching Bratton, they said, `Hey, we can do something about this.' ''

That represented an important change in attitude, he said, because there was a widespread view 10 years ago that the police could not do much about crime but respond to it. ``Now that has changed,'' Blumstein said. ``The police feel they can do something. It has changed their deployment, their tactics and the way commanders hold lower levels responsible for reducing crime.''

The FBI's crime index is composed of four violent crimes (murder, robbery, aggravated assault and rape) and four property crimes (burglary, motor vehicle theft, arson and minor larcenies like shoplifting).

Murders dropped 7 percent in the first half of 1996, robbery and aggravated assault declined 5 percent, and rape and larceny 1 percent. Arson was the only offense to increase, by 2 percent.

President Clinton issued a written statement saying that some credit for the continued decrease should be given to his sponsorship of the ban on assault weapons, to Cthe Brady law and to his plan to put more police officers on the streets.

``At the beginning of my administration,'' Clinton said, ``we set out to change this country's approach to crime by putting more officers on our streets through community policing, and taking guns out of the hands of criminals. We are making a difference.''