Maggots Solve Murders : Entomologists Help Police to Really Bug Criminals

Not to offend, but this is about maggots and the good things they do.

You see, maggots help solve crimes.

To the faint of heart or weak of stomach, fear not. Graphic description is not the intent here. It is only to give the writhing, squishy larvae their due, for maggots, which evolve into the common fly, are one of the chief tools in a relatively new brand of sleuthing called forensic entomology.

It is a field that is growing. Police investigators who once raised an eyebrow of disbelief at the idea now call on bug experts much more frequently.

Links to Crime Scene

Many is the criminal who wishes that bugs had never been found to have such gumshoe qualities. Maggots have proved instrumental in establishing the time of death in some puzzling murder cases, and other bugs have linked criminals to a crime scene.

“Who would ever think that a maggot could be a witness?” said Dr. Bernard Greenberg, one of the foremost experts in the field and a professor at the University of Illinois campus here.

Like most of his breed, Greenberg stumbled into the world of forensics by accident. His entomological specialties are flies and (do we dare enter this into the equation?) cockroaches. About 13 years ago, he received a call from a young state’s attorney in Chicago, whose case was somewhat thin, in part, because of the difficulty in pinpointing the time of death of two murder victims who had been killed in the late summer three years previously.

Case Study Cited

Pathologists have several methods for determining a time of death, but the techniques become less accurate with the passage of time. But, knowing flies as well as he did, Greenberg quickly recognized in morgue photos the maggots from the eggs of the green blowfly (Phaenicia sericata), the city slicker of flies.

After factoring in the temperature during that period, which affects the growth of maggots, Greenberg estimated the time of death within two days. His testimony, along with that of others, led to the conviction of the two men accused of the crime.

Thus, after years as a pure scientist, Greenberg suddenly found himself in the world of criminology and courtrooms.

“In a way, it’s the capping of my career,” he said. “It’s really only recently that forensic entomology has begun to have some recognition.”

Only One Book on Subject

Today, there are only a handful of criminal bug men in the country, and only one book on the subject--by British entomologist Kenneth Smith--has ever been written. Forensic entomologist Robert Hall of the University of Missouri estimates that there may be no more than a dozen of his kind in the world.

“It requires someone who’s just a little bit odd to begin with,” he said.

Essentially, their specialty is to be so familiar with bugs that they can calculate life cycles in great detail, from the time eggs are laid until they move into the next phase of development. And, they must also know where certain bugs come from.

One example of that occurred in New Zealand in 1982, when authorities confiscated 188 kilograms of marijuana--at the time the country’s largest drug bust. Although authorities suspected that the pot had come from Asia, they couldn’t prove it, thus failing to make a case for the more serious charge of importing narcotics.

Bugs Found in Marijuana

After chemical tests failed to turn up anything unusual, the police turned the case over to a government entomologist. The result: 61 bugs were found in the marijuana and only one was known to be common to New Zealand. By doing a map overlay, the entomologists determined that the plants had been grown about 150 miles northwest of Bangkok. The drug dealers were convicted of importation.

In another 1982 case, a woman was found murdered in Ventura County. As investigators walked around the murder scene, they discovered that they were all getting red welts on their legs. When an entomologist was called in, he proclaimed the welts to be chigger bites.

As it turned out, chiggers are indigenous only to very small areas of the state. When police began rounding up possible murder suspects, one of them had the same welts on his legs as did the police officers. When asked about the bites, the man said he had gotten them in his own neighborhood.

The police determined that there were no chiggers where the man lived. He was found guilty of murder and sentenced to life imprisonment.

The first documented case in which the lowly maggot was used to pinpoint a very specific time of death occurred in Scotland in 1935. Two women had been brutally murdered and left in a ravine. Any way of identifying the victims had been removed.

Doctor Had Alibi

The case, one of the more celebrated of the day, eventually led police to the home of a Lancaster doctor, whose wife and the family’s nursemaid had not been seen in some time. As the evidence mounted against the doctor, a major problem was the time of death, which police had set on a day when the doctor had an alibi.

Authorities turned to Alexander Means, an insect specialist at the University of Glasgow, who calculated how long it would have taken the maggots on the victims to reach maturity and theorized that police had placed the time of death four days later that when the women were actually killed.

The doctor was brought to trial and found guilty of the murders, thanks in large measure to the information that Means provided.

In more recent times, forensic entomologists have been used in a number of different ways, from lawsuits over food spoilage to investigations into the amount of time termites have infested buildings. But, by far the most interesting--and somewhat macabre--cases continue to be those involving murder.

One of the leaders in that field is Greenberg, who has written two books on flies and keeps a collection of mammoth cockroaches--almost large enough to cover his palm--in his laboratory. The two happened to be his greatest phobias growing up as a child.

Since he received the call from the state’s attorney in 1976, Greenberg has testified in 11 criminal cases and given opinions in 38 others. Perhaps his most noted one was a 1984 serial murder case in which eight people were killed in a six-state spree by a man named Alton Coleman.

One of those murdered was 9-year-old Vernita Wheat of Kenosha, Wis. Her mother had allowed Coleman to take her to a carnival. Three weeks later, her body was found in an abandoned building in Waukegan, Ill. Part of Coleman’s defense was that there was no way to tell exactly when the girl was killed. But Greenberg was able to study the body, backtrack and place the time of death on the night that she was taken to the carnival. Coleman was convicted of the murder.

‘The Bug-Less Woman’

Another case that he is expected to testify in involves the murder of a woman who was found bludgeoned to death in her apartment. Greenberg calls this one the case of the bug-less woman because flies had not yet laid their eggs on the corpse, although the windows and door were open.

The boyfriend of the woman told police that the scene was as he had found it. But an autopsy showed that the woman had been dead for 12 hours. Greenberg will testify that the apartment could only have been opened moments before the police arrived, thus making the boyfriend a chief suspect.

Despite the rather bizarre nature of his work, Greenberg maintains a sense of humor about it all.

And let there be no doubt about what he thinks of flies, even after all these years of studying them. A fly is at its best when it is inside a cage in his laboratory.

“I like flies in their place, and their place is behind bars,” he said, picking up a red plastic fly swatter. “If they get out, it’s capital punishment. There’s no negotiation.”