Police have long contended that drug abusers are likely to commit street crimes. A Justice Department study last week revealed the extent of the problem: half to three-fourths of the men arrested for serious crimes in a dozen U.S. cities had recently used drugs. In New York City, 79% of those tested had used cocaine, marijuana or some other illegal substance. In Washington the proportion was 77%, in San Diego, 75%. Those figures were "much higher than anyone had anticipated," said James Stewart, the study's director. "If we are going to do something about the crime rate, we are going to...

