48 Years Later, Bugs Clear Convicted Murderer
With help of maggots, entomologists show murder occurred later than believed.
Oct. 24, 2007 -- A man who was convicted 48 years ago of the hideous rape and murder of a 12-year-old girl has finally been exonerated, but it took a few hundred flies and the young science of forensic entomology to win his freedom.
Steven Truscott was only 14 years old when he was sentenced to die in Canada by hanging for the murder of a childhood friend, Lynn Harper.
His sentence stimulated debate over the death penalty, primarily because of his youth. Although this debate contributed to the abolition of capital punishment in Canada, Truscott still served 10 years in jail and has spent the rest of his life living in the shadow of an unwarranted conviction.
Attorney James Lockyer of Toronto argued passionately before the Ontario Court of Appeals on behalf of Truscott, who has proclaimed his innocence over all these years, and in the end the court agreed with those claims, at least partly.
Last month the court quashed the conviction, labeling it a "miscarriage of justice."
The ruling wasn't a surprise to entomologist Richard Merritt of Michigan State University -- one of a dozen certified forensic entomologists in the United States -- whose testimony in the trial was "critical," according to Lockyer. The proof, Merritt argued during a rigorous seven hours testifying, was provided by the flies that would have landed on the young girl's body within minutes of her death.
"I was brain dead at the end," said Merritt, who has become somewhat passionate in his defense of Truscott.
"It was a horrific crime," he said in an interview. "I could never imagine how this kid who went to school with this girl and was a friend of hers could have done this."
Truscott was the last person seen with Harper, late in the afternoon of June 9, 1958. She was a passenger on his bike on the outskirts of their Canadian village. Her body was found two days later near the place where the two had been seen. Lynn had been raped and strangled with her own blouse.
Timing became key in the trial and subsequent appeals of the case.
"The time of her death has been the subject of intense controversy from the outset," the court observed in rendering last month's verdict.
Numerous witnesses testified that they saw the two youngsters riding on the bike at around 7 p.m., and Truscott was seen alone at about 8 p.m. So if Truscott did it, the murder had to occur during that narrow window between 7 p.m. and about 8 p.m.
The pathologist who conducted the autopsy put the time of death at precisely between 7:15 and 7:45 p.m.
John Penistan based that conclusion primarily on the examination of the food contents in her stomach, which he testified had been in Harper's body less than two hours at the time of her death. During the appellate court appeal, several experts testified that stomach contents are subject to many variables, including temperature and the nature of the food and many others, and thus could not be a reliable way of determining the precise time of death.
Merritt is more blunt in his assessment. "It was crap," he said.
Sadly, in a handwritten memorandum that Penistan himself called an "agonizing reappraisal," he admitted that he spoke with too much confidence during Truscott's trial, and his own evidence did not rule out the possibility that the murder could have occurred several hours later, when Truscott was at home.
That memo, which only surfaced recently, was written seven years after the conviction, while Truscott was still in prison serving a life sentence.
Tragically, the issue might have been resolved quickly in a court today. DNA evidence could have ruled Truscott out as a suspect, but no DNA evidence remained from the death scene. So Lockyer turned to the relatively new science of forensic entomology.
Merritt and Sherah VanLaerhoven, a forensic entomologist for the province of Ontario, were able to show to the court's satisfaction that their evidence indicated the death occurred much later, probably the following day, at a time when Truscott was known to be somewhere else.
The two scientists were fortunate in that the court record contained several photographs and precise measurements of insects that "colonized" the body moments after death. Chief among them were blow flies that laid hundreds of eggs, beginning soon after they found the body. The life cycle of the blow fly is well known, so it was possible for the scientists to work backwards from the time that the body was discovered to the time when the flies first colonized the body.
That would give them a fairly good fix on the time of death.
"We were able to determine how long it had been since colonization had taken place," Merritt said.
They did that by measuring the size of the larvae, or maggots, in the early photographs. They found that the maggots were not nearly as large as they would have been if they had been present on the body since the early evening of June 9.
Both testified that Lynn was most likely killed the next morning, not during the narrow window the night before when it was possible that Truscott could have been the killer.
Since the time of death weighed so heavily on the minds of jurors nearly half a century ago, the appellate court ruled that the conviction had to be set aside. Lockyer and his fellow attorneys argued that simply reversing the conviction wasn't enough. They wanted the court to go one step further and declare Truscott innocent.
But the court said it had no way under Canadian law to declare someone innocent. The best it could do is to toss out the conviction. The court also said it was not possible to retry the case in a lower court because so many of the witnesses are now dead. The result would most likely be acquittal, which is where the matter stands now.
All these years later, Truscott, who doesn't talk much any more about his ordeal, is free and not guilty, but still has not been declared innocent of a murder that science said he could not have committed.
Lee Dye is a former science writer for the Los Angeles Times. He now lives in Juneau, Alaska.