King Tutankhamen became big news in February, more than three millennia after his death, when newly released DNA analyses indicated that he probably died of malaria. For Howard Markel, though, the Tut study raised as many questions as it ­answered.

“Respecting the dead after burial is sacred across all ethnicities and religious beliefs and time periods,” said Markel, director of the Center for the History of Medicine at the University of Michigan. “Does a famous person lose that?”

In Markel’s view, the decision to dig up human remains ought to depend on whether the re­search would enhance our knowledge of history or our under­standing of disease today. The Tut study satisfied both criteria, he said: It revealed not just a cause of death but also vast information about King Tut’s family tree. It also yielded some of the earliest examples of the malaria parasite, and thus the opportunity to learn how the parasite has changed over ­time.

Not all such studies will qualify. “Some people have wondered if Abraham Lincoln had Marfan’s disorder [an inherited connec­tive-tissue disorder],” Markel said in an interview. “Does that really change our knowledge of Lincoln, what he did, how he conducted the Civil War? Someone asked me whether we should dig up Isaac Newton and see if he had Asper­ger’s syndrome. Well, we don’t have a gene for Asperger’s.But even if we did, how would that change our understanding of Newton’s contributions or his brilliance or anything else?” In Markel’s view, the dead should be disturbed only for good ­reasons.

But what if it’s the dead who disturb the living? That can depress property values, Eric J. Gouvin writes in Law and Magic: A Collection of Essays (Carolina Academic Press). In two in­stances, courts tried to protect unwary buyers. In California in 1983, a judge held that a house’s grisly history—10 years earlier, a woman and her four children had been murdered ­there—­consti­tuted a material defect that the seller should have disclosed. In New York in 1991, a court can­celed the sale of a Victorian home because the seller had failed to reveal that many people consid­ered the place haunted; indeed, the seller herself had talked publicly of supernatural visitations. “Applying the strict rule of caveat emptor to a contract involving a house possessed by poltergeists,” the New York judge said, “con­jures up visions of a psychic or medium routinely accompanying the structural engineer and Ter­minix man on an inspection.” The seller should have revealed that the house was believed to be ­haunted.

Alarmed by the rulings, real estate agents began lobbying. According to Gouvin, many states enacted laws stipulating that sellers need not disclose a home’s “psychological” defects. Oregon passed a law saying that a seller was not required to reveal that the property had been the scene of a crime, and witchy Massachusetts excused sellers from disclosing any “alleged parapsychological or supernatural phenomenon.” Haunted-home buyers, unable to get relief from judges, now must seek out ­exorcists.