Sniper’s sloppiness may help hunt

Serial murderers have often been undone by a sloppiness that increases as their crimes continue.

Experts believe the same pattern may become the undoing of the sniper who has killed nine people in the Washington, D.C., area since Oct. 2. Though crafty in many ways, the sniper has put himself at risk, experts say, by apparently using the same weapon and vehicles over and over.

In his most recent attack, on Monday night, he ventured close enough to a crowded mall in Fairfax County, Va., that some shoppers could have seen him. As time passes, ‘‘it looks like he’s getting a lot sloppier,’’ said Michael Rustigan, a criminologist at San Francisco State University.

Washington’s serial killer is all but unique in the annals of crime, because he apparently picks his victims at random, enabling him to frighten a metropolitan area in a way that few killers could. But he is a serial killer all the same, meeting the FBI definition: Three or more victims with a ‘‘cooling-off period’’ of unspecified time between the murders.

There have been a large number of murderers who have killed a number of victims at one shooting, such as George Hennard, who killed 22 people and wounded 23 in his armed attack on a Killeen, Texas, cafeteria in 1991. And there have been many others who killed over an extended period, such as ‘‘Son of Sam’’ slayer David Berkowitz and Ted Bundy.

Such serial killers usually pick one category — such as women or minorities — as their victims. But experts say it is highly unusual for a killer to attack strangers picked at random in a concentrated period, as the sniper has in the last two weeks. The concentrated timing adds to the terror, they say. The fact that he is picking strangers makes it tougher for police to track. (LATWP)