Once a medical technician at a hospital, Lupoe recently had been fired, owed thousands of dollars and was a month behind on his mortgage payments.
Detective David Cortez of the Los Angeles Police Department told The Associated Press that Lupoe, not the economy, was to blame for the tragedy.
"Being there and walking through the crime scene, it's a lot easier to see him as the suspect that did this to other people than, the economy did this to him," Cortez said. "It's how he chose to respond to the circumstances; he had options."
Long before the Lupoe and Pardo tragedies, another California family murder-suicide made headlines. In June 2007, California businessman Kevin Morrissey, 51, shot his wife and two daughters in a parked car before turning his handgun on himself.
Police investigating the deaths said they found a note in which Morrissey, who ran a skin-care clinic with his wife, said he was distressed over his family's financial situation.
Experts say that men who lose the ability to support their families may be anguished to find their status as "breadwinner" compromised.
"The idea, somehow, that a man is not able to support his family, is less of a man, those ideas might be cultural determinants" for suicide, said Yeates Conwell, a professor of psychiatry at the University of Rochester Medical Center in New York.
While Morrissey, Pardo and Lupoe are dead and cannot explain their motives, Thomas Wayne Garrett, 59, of Oklahoma, has been quite clear. He told police that he shot his wife because he didn't know how to tell her they'd been evicted.
Multiple medical problems had left Garrett's wife, Cynthia Garrett, hospitalized for 10 days in December. During that period, the Oklahoma County Sheriff's Office evicted the couple from the home they rented in Midwest City after they didn't pay their rent.
Garrett had been out of work for several years after losing his job at a tire company.
Midwest City Police Chief Brandon Clabes said that after the shooting, Garrett told police the day he picked up his wife from the hospital, he drove around their neighborhood, not knowing how to tell her that they did not have a home to return to.
Eventually, he pulled over and shot her with a .38-caliber handgun.
The bullet, Clabes said, entered Cynthia Garrett's left breast and ripped through her lung before settling in her chest cavity.
"He realizes she's suffering, so he drives her to the emergency room," Clabes said, adding that Garrett told police his plan had been to kill his wife and then himself.
"It's a really sad case all around," he said.
Fear of eviction has led to shooting tragedies in at least two other states.
In Massachusetts, Carlene Balderrama, 53, fatally shot herself with her husband's rifle just before her home was to be sold at a foreclosure auction.
In Ohio, Addie Polk, 90, shot herself after facing eviction. Polk survived and the mortgage financing company Fannie Mae later forgave her loan.
Abroad, the suicides of three well-known businessmen apparently were caused not by unemployment or foreclosure, but steep fiscal losses and business-related stress.