Science Undermines Oleander Murder Case : Inquiry: A prosecutor’s doubts about his evidence and a gamble by the defense led to the dismissal of poisoning charges.


Prosecutors once hailed it as the first oleander poisoning case ever taken to court--a tangled tale of the death of a Burbank mortician that promised to become a sensational murder trial.

But the case of the People vs. David Wayne Sconce, which was dismissed last week in Ventura County Superior Court, began to fall apart early this year, undermined by the very force that created it: science.

It was a Philadelphia toxicologist’s tests showing oleander in the dead man’s remains that led to Sconce’s arrest; and it was a New York professor’s finding of no oleander that prompted Sconce’s release.

But the different test results are only part of the reason Sconce is a free man today. Attorneys say the case might have gone to trial anyway but for two things: the doubt that a young Ventura County prosecutor felt about his own evidence, and the willingness of Sconce’s attorney to take a gamble.


Sconce, 35, was accused of using extracts from the poisonous oleander bush to kill a business rival, mortician Timothy R. Waters, who died at his mother’s home in Camarillo six years ago.

At the time, Ventura County officials attributed Waters’ death to his weight--more than 300 pounds. But in the next few years, investigators in Los Angeles County began to suspect that Sconce had poisoned Waters.

The motive for murder, they said, was to keep Waters from reporting violations at Sconce’s crematorium in Altadena. Sconce had admitted hiring two thugs who beat up Waters two months before he died.

The method of murder, investigators said, was oleander, a common flowering bush whose leaves can be deadly. An informant told police that Sconce had bragged about spiking the dead man’s drink with poison. Then they learned that Sconce had a book describing oleander as a hard-to-detect poison.


The proof of murder, or so it seemed, came in 1988, when Frederick Rieders, a Philadelphia toxicologist, reported finding oleander in Waters’ remains. The Los Angeles County district attorney’s office was ready to charge Sconce with murder.

The problem was, where did the alleged murder occur?

There was no evidence to show how or where any poison had been administered. Eventually prosecutors decided that the charge should be filed in Ventura County, where Waters had died.

Ventura County Dist. Atty. Michael D. Bradbury agreed to file the case in February, 1990, and deputized two veteran Los Angeles County prosecutors, Harvey Giss and James Edward Rogan, to handle it.

Los Angeles County had already convicted Sconce on a number of charges, including the assault on Waters, and the district attorneys in both counties decided that Los Angeles prosecutors should handle the Ventura County case.

But late last year, Rogan was appointed to a judgeship. Rather than ask for another Los Angeles County prosecutor, Bradbury decided to appoint one of his deputies, Kevin G. DeNoce, to assist Giss.

One reason cited at the time was convenience. With DeNoce already in Ventura, Giss would not have to drive 70 miles to handle a routine pretrial hearing.

Giss had just been voted “Prosecutor of the Year” by the California District Attorneys Assn. DeNoce was three years out of Pepperdine University’s law school. But DeNoce brought to the case a scientific background that proved to be crucial.


“Giss asked me if I was willing to handle the toxic and scientific aspects of the case,” DeNoce recalled last week. “My job was proving that the victim was murdered. His job was proving that the defendant was the one who did the murder--all the circumstantial evidence and motive.”

After reading the 2,000-page transcript of Sconce’s preliminary hearing and studying Rieders’ test results, DeNoce was worried.

“I became concerned that the Rieders methodology was not necessarily substance-specific,” he said.

In other words, something besides oleander could have triggered the positive result in Rieders’ tests. “You need a substance-specific test where you can actually look at a molecule and say, ‘That’s oleandrin,’ ” DeNoce said, referring to the active ingredient in oleander.

He took his concerns to Norman Wade, acting director of the Ventura County Sheriff’s Department Crime Lab. “I advised him to get better tests,” Wade said last week. Wade and DeNoce began a nationwide search for the best laboratory to do the work.

But Sconce’s attorney, Roger Jon Diamond, was a few steps ahead of them.

Diamond said he had decided on his strategy: Rather than try to prove his client innocent, he would try to prove there was no murder. In early December, Diamond persuaded Ventura County Superior Court Judge Frederick A. Jones to let him exhume the body so a defense expert could examine tissue samples.

Diamond was referred to Jack Henion, a Cornell University professor. But before Henion agreed to do the work, he got a call from DeNoce, whose search for the best testing had also led to Cornell.


“About halfway through the conversation,” DeNoce recalled, “he said, ‘By the way, I’ve been contacted by another expert retained by the defense . . . and they might want to use me, too.’ ”

DeNoce said he didn’t object to both sides using the same expert. Diamond said he thought about raising legal objections but quickly changed his mind.

“Our decision to let them use Henion was the key strategic decision for the defense,” Diamond said. But it was a risky decision:

If Henion came back with the slightest finding of oleander or one of its byproducts, Sconce would be doomed. But if the scientist found no sign of the poisonous shrub, “how could they repudiate their own expert?” Diamond said.

Both sides agreed that Henion’s methods and equipment were the best available. Using exotic processes known as liquid chromatography and mass spectrometer analysis, he claimed he could find oleander in amounts as little as 30 parts per billion.

Henion received two sets of tissue samples, one taken immediately after Waters died, the other when the body was exhumed.

“We wanted both so there would be no question,” Diamond said. “We wanted every possible piece of evidence examined.”

Henion’s tests were based on precise measurements of the weight of molecular particles, while Rieders’ were essentially behavioral: If it looked like oleander and acted like oleander, it must be oleander.

One of Rieders’ testing methods, for example, analyzed the tissue samples by how they behaved in a chemical solution. In extremely simplified terms, he first took a sample of oleandrin, placed it in a solution, inserted a plate and observed how far the oleandrin molecules climbed up the plate.

Then he did the same thing with Waters’ tissue samples. Some of the molecules behaved exactly as the oleandrin molecules.

“My concern,” DeNoce said, “was that it’s possible that two different molecules can behave the same way . . . and still not be the same thing. That’s what bothered me.”

In his tests, Henion figured out how fast an oleandrin molecule moves under certain conditions and subjected the tissue samples to the same conditions. Molecules that moved at the same speed as oleandrin were isolated for further testing.

The next set of tests subjected the suspect molecules to bombardment by electrons, which broke the molecules into ions. The ions were weighed and compared with the weight of ions broken down from oleandrin molecules. The weights didn’t match. The samples contained no oleandrin, Henion concluded.

“According to the experts, that’s as definite as you can get,” DeNoce said. “We know it’s not there now, and it’s unlikely that it was ever there. I accept that it probably was never there.”

Even with the conflicting test results, DeNoce said prosecutors considered taking the case to trial anyway and making it a battle of expert witnesses. But he agreed that it would have been awkward for prosecutors to challenge Henion’s results when they had paid half of the $20,000 cost of the tests.

Eventually Bradbury decided to dismiss the case for now and check the remains for other poisons.

DeNoce said Giss supported his call for a new test, even though it resulted in dismissal of the case. “I was the new player . . . but Harvey Giss was always receptive to my critique of the case,” DeNoce said.

He said he is now trying to determine whether any other poisons mentioned in Sconce’s book on toxic substances would cause the same symptoms that Waters exhibited. Testing for other poisons could take years and would cost about $20,000 per substance tested, he said.

Already under criticism by the Board of Supervisors for exceeding his annual budget, Bradbury said he would ask Los Angeles County to help pay the cost.

Diamond maintains that there was no murder, but he said he respects both Giss and DeNoce.

“DeNoce strikes me as being a very ethical prosecutor,” Diamond said. “He seems to be very concerned about arriving at the truth.” Giss also seems “sincere in not trying to frame an innocent person,” Diamond said.

“That’s what’s so scary,” Diamond said, “that the legal system can make such a mistake.”