It's a terrible way to solve a crime: Investigators learn more about the sniper roving metro Washington and get closer to an arrest each time the killer strikes.
The manhunt has been exasperating for its shortage of clues and the steady stream of victims. But being meticulous and quick does not make the killer uncatchable.
In fact, even cases that seem inscrutable are often solved with key help coming from alert citizens, increasingly sophisticated sleuthing, and, sometimes, hubristic assists from the criminals themselves.
Ultimately, the key to solving the deadly puzzle in suburban Maryland could be something as simple as a tip about a remembered slight or a slip by a shooter perhaps intoxicated by his own success.
To be sure, progress has seemed slow for hundreds of law enforcement officials now on the case. The shooter, possibly aided by a driver, has left few clues other than the bullets themselves. His targets have been random, making a clear profile of the perpetrator difficult to draw.
"We've never really had this type of event occur," says John Cohen, a security consultant from Rockville Center in Maryland. "It's a nightmare scenario for law enforcement."
Such indiscriminate sniping is usually associated with war zones like Bosnia, where it's used against the civilians to intensify the horror of the conflict.
In this country, serial shooters have most often been motivated by hate such as when Buford Furrow shot up a Jewish Community Center and killed a postal worker in the Los Angeles area in 1999. Or bursts of outright madness, such as when Charles Whitman gunned down 16 people from the observation deck at the University of Texas Tower in 1966.
Indeed, for almost every instance experts have pointed to as a possible analogy, they are as quick to say how this killer is different.
His seemingly patient, methodical targeting of individuals has been compared to David Berkowitz. Known as Son of Sam, he killed six and wounded seven in New York City in 1977. It wasn't until the fourth shooting that police noticed a pattern and tied his victims together by the .44 caliber bullet used.
Berkowitz was caught after police tracked down a parking ticket he got at one of the scenes. But Berkowitz's shooting spree took place over months, not days as in this case. And his victims had something in common, they were young women, either alone or sitting in parked cars with their boyfriends.
THIS roving sniper has also been compared to the Theodore Kaczynski, the so-called Unabomber, because of his preference for using a powerful weapon and keeping a distance from his victims.
"He likes a sense of power and anonymity that comes with using a high-powered rifle," says Brian Levin, a criminologist and director of the Center for Hate and Extremism in San Bernardino, Calif. Mr. Kaczynski had a clear political motive he was antitechnology and targeted victims accordingly.
The randomness of these attacks, involving young and old victims of various races and ethnicities, leads some experts to believe that this killer is motivated by narcissism and the need for self-aggrandizement.
That, too, fits in part with a profile of the Unabomber that former CIA psychological profiler Jerrold Post did during the 17 years Kaczynski was at large. Dr. Post says that while Kaczynski did have a political agenda, his real motive was self-satisfaction. With his personal life in shambles, he was able to build deadly bombs and outsmart the police and the FBI for years.
"One of my conjectures was that each morning he would look into a mirror, just as Snow White's stepmother did, and say, 'Mirror, mirror on the wall, who's the biggest serial bomber of them all?' And the answer would always come back: 'You are, Unabomber,' " he says. "One day the answer came back 'Timothy McVeigh,' and that I think enraged him, and ... led to the acceleration of his pattern."
Mr. Levin believes this roving sniper also gets a "sense of power and a thrill" from being able to outsmart authorities, but with a difference: This killer may be someone who tried to play by the rules and nothing seemed to work out for him. His career and relationships with women were probably frustrating and unsatisfying. "This person is kind of a wallpaper white male, a disenfranchised, disrespected man who's getting back at society," theorizes Levin. "That's one of the reasons he's kept his distance from inner D.C., where he might loose his cover."
Other criminologists have a more chilling profile that this killer or these killers are simply engaging in a cold-blooded sport.
The reason is the randomness. This does not appear to be motivated by racial hatred, as recent killings in Chicago and Pittsburgh were. "This is a spree shooter who doesn't appear to have any clear-cut motivation," says James Alan Fox, a criminologist at Northeastern University in Boston. "If there's two shooters, which would not be surprising, then it's a team sport.
Staff writer Faye Bowers contributed to this report.