IHOP shooting: Will police ever understand gunman's motive?

As police in Carson City, Nev., seek a motive in the IHOP shooting Tuesday, criminologists say thorough investigations can often turn up the reasons behind mass killings.

Authorities in Carson City, Nev., are still searching for the gunman’s motive in Tuesday's shooting rampage at an IHOP restaurant. As they do, criminologists are suggesting that investigations could yet uncover why the shooter stepped from a minivan with a yellow "Support Our Troops" sticker on it and proceeded to kill five people, including three members of the National Guard.

Often, there is a pattern to be discerned by seemingly random mass killings, undercutting the notion that somebody “suddenly snaps and goes berserk and then shoot at anything that moves,” says James Alan Fox, a criminologist at Northeastern University in Boston and author of “Extreme Killing: Understanding Serial and Mass Murder.”

“These mass killings tend to be well-planned and methodical and deliberate and selective,” says Professor Fox. “Although we may never know in this case, my hunch is that the choice of location and perhaps even the victims was not just random.”

Just before 9 a.m., the gunman, since identified as 32-year-old Eduardo Sencion, stepped from his van in the parking lot of the IHOP and opened fire. Then, he continued into the restaurant and marched toward a table of five uniformed National Guard members, shooting each one, fatally wounding three of them, authorities said.

Five people were killed in the attack – including the gunman, who shot himself – and seven were wounded, authorities added.

Investigations can sometimes lead to an understanding about why such rampages occur, says Fox. After the the 2006 Capitol Hill massacre, in which a 28-year-old perpetrator shot himself after killing six and wounding two, Fox and a team of investigators began following several leads.

“We actually came up with a letter he had written and disposed in a dumpster, telling his brother what he was going to do and why,” Fox recalls.

It is common in these situations that the shooter is someone who has found his life to be miserable and so is therefore willing to take his own life. “Even though these shooters kill themselves, it is common that they go after others who in some way they hold responsible for their misery,” Fox says.

But he cautions against jumping to conclusions.

"Even though it appears that many he shot in the restaurant were uniformed, and he had a 'Support the Troops' sticker on his car, we can only imagine the connection he might have had,” Fox says. “We don’t know who put the sticker on his car or when, and we can’t rule out that he was targeting the military."

Among the information that has emerged about Mr. Sencion is that he filed for bankruptcy in 2009 and had been living in Stateline, a casino town on the California border. A report by a local CBS affiliate also says that his family claims Sencion has had "mental issues."

That could raise scrutiny about the quality of mental health care in the US, which began to dwindle with the deinstitutionalization movements of the 1980s and '90s.

“We have more mentally ill people than ever before who are not receiving proper care and treatment,” says Charles Williams, director of the Center for the Prevention of School-Aged Violence at Drexel University in Philadelphia. “You can’t even find [a psychiatric hospital] anymore.... So we saved public dollars in the short-term but could be compromising public safety in the long term.”