After Nicole Brown and her friend Ron Goldman were stabbed to death at Brown's Brentwood, Calif., home in 1994, the property sat on the market for more than two years waiting for a buyer.
The home eventually sold for $200,000 less than what Brown had originally paid for it.
"If the murder was infamous, the property value could certainly go down," said the NAR's Helmon. "That creepy feeling will have an adverse effect on the value of the home."
Immel said that in the case of the San Diego mansion where 39 members of the Heaven's Gate cult killed themselves, the price of the property declined as much as 50 percent when it was resold.
"The price depends on the severity of the stigmatization," said Immel. "Murder would seem to be horrific and would garner a 50 percent reduction, whereas a landslide on the property might be more toward 30 percent."
If the event that an elderly person died at the home from natural causes, Immel said it's unlikely to detract from the value of the home.
While homeowners may assume that they would have heard about a murder that took place at a specific home or in a neighborhood, or may count on their broker to inform them of one, Immel advises buyers to err on the side of caution.
"Because these disclosure laws regarding stigmatized homes vary from state to state," said Phil Immel, a California real estate broker. "Be a proactive consumer and ask lots of questions.
"You don't want to live in a haunted house, do you?"