If it really was the Washington, D.C.-area sniper who left the handwritten message, "Dear policeman, I am God," near a shooting scene, it could be the latest in a tradition of boasts by serial killers to authorities on their trail.
"Most serial killers are quite full of themselves," says Mike Rustigan, a criminology professor at San Francisco State University who has interviewed serial killers. "The prime mover with this guy, I'm sure, is the monstrous ego. He likes the attention. He loves the game."
Some, like the Unabomber, Ted Kaczynski, got tripped up when they started boasting about their crimes in writings. Others, like San Francisco's Zodiac Killer, thumbed their nose at authority and seemingly got away with it.
"If you look at any of the interviews of [Ted] Bundy, you see that same cockiness," Rustigan says. "The only guy where I didn't see much of that was Jeffrey Dahmer. [He was] quite humble."
Read more about past serial killers who taunted authorities.
Police found the possible message from the sniper on a "death" tarot card, with a bullet casing nearby, in a wooded area about 140 yards from the site where a 13-year-old boy was shot and critically wounded Monday in Bowie, Md.
Monday's shooting is believed to be one of a series of at least eight sniper attacks — six of them fatal. Authorities are trying to determine if a fatal shooting Wednesday at a Manassas, Va., gas station also is connected.
Police would not publicly offer details about the tarot card find, but on Wednesday they were visiting magic and novelty shops asking questions about tarot cards and who may have purchased them recently. In addition, ABCNEWS has learned the card contained a handwritten request from the sniper that it not be revealed to the media.
But some voice skepticism over whether the card actually came from the sniper.
"Someone who has been watching this thing might have, in some way, as a prank, left this thing behind," says N.G. Berrill, a forensic psychologist and faculty member at John Jay College of Criminal Justice in New York. "My gut says it's not [real]. It could be wrong."
While Rustigan argues that many serial killers are arrogant and boastful, he and Berrill agree they often have different motivations and do not always communicate to police in the same way.
Many serial killers, like David Berkowitz, the Son of Sam — who proclaimed in a note, "I am a monster. I am the Son of Sam" — shot their victims at close range, ranted in their communications and behaved psychotically.
Others, like San Francisco's Zodiac Killer, who also killed at close range, taunted the authorities and the media as if it were an ego-building game, rather than a rant.
Still others, like the Unabomber, killed at a distance. The Unabomber methodically killed his victims by constructing homemade bombs and sending them through the mail. His rambling communiqué, a 35,000-word manifesto, was laden with political messages and railings against technology.
Along those lines, a "death" tarot card with an outrageous boast might be too showy for the current sniper, who also kills from a distance, Berrill says.
"If he left it … it would possibly change the dialogue as to what this person is about," Berrill adds. "He's like a marksman. He's stealth. He's hidden. He's demonstrating what kind of cat he is. … So why would he then drop a dopey card on the ground?"