OMAHA, Neb. — As the chief crime scene investigator for Nebraska's busiest county for more than a decade, David Kofoed helped put away hundreds of criminals using cold, hard science. He developed a reputation as a man who could find things others couldn't.
But the Douglas County CSI director's conviction Tuesday for planting blood evidence during a murder investigation threw into doubt the legitimacy of other cases he worked on, and some of those he helped put behind bars are likely lining up to appeal.
"I think that process has already begun," Clarence Mock, the special prosecutor in Kofoed's case, said Wednesday.
Douglas County prosecutors, wary of a potential flood of appeals, were quick to say they reviewed past cases and believe the 53-year-old Kofoed only planted evidence in the investigation for which he was convicted.
But one man convicted of murdering his young son has challenged Kofoed's work since the investigator was charged last April. And Chief Deputy Sheriff Marty Bilek said sheriff's department officials are prepared to respond as criminal defense attorneys seek review of Kofoed's past cases.
"It's a very unfortunate circumstance, but it would behoove attorneys who have cases that involved Dave Kofoed to re-examine them and we'll cooperate with any attorney who wishes to do that," Bilek said.
Kofoed's work came into question after his 2006 investigation into the slaying of a rural Cass County couple, Wayne and Sharmon Stock. Detectives zeroed in on the couple's nephew and his cousin, but found no physical evidence tying the two to the killings. They managed to get a confession from the nephew, but he retracted it the next day. A day later, Kofoed said he found a drop of one of the victims' blood in a car linked to the suspects that had already been combed over by another forensic investigator.
The suspects were charged with murder and jailed for several months before being released because prosecutors determined the confession was unreliable and didn't fit the facts of the case. A man and woman from Wisconsin eventually pleaded guilty to murdering the couple and are serving life prison terms.
The FBI began investigating Kofoed after the slain couple's nephew filed a lawsuit alleging civil rights violations. The agency's findings led to the evidence tampering charges against Kofoed.
During his trial, Kofoed blamed the speck of blood found in the car on accidental contamination. But Cass County District Judge Randall Rehmeier said he didn't buy it, and that the evidence showed Kofoed intentionally planted the blood in the car.
Before issuing his verdict, Rehmeier said there were similarities between that investigation and one in which a man, Ivan Henk, was convicted of murdering his young son, whose body was never found.
In both cases, there were confessions by the suspects and a lack of physical evidence to corroborate them until Kofoed found a speck of blood that had previously been overlooked, the judge said.
Henk challenged his conviction after Kofoed was charged, saying Kofoed planted the evidence in his case, too. But a judge ruled that Henk was convicted on the strength of his two confessions - one made in court and the other to detectives - not the blood Kofoed found. Henk is appealing.
Kofoed has not been charged in any other investigation. He remains free on bond, but is due back in court in May for sentencing. He faces up to five years in prison and a $10,000 fine. Kofoed has not responded to a request for comment made to his attorney, Steve Lefler, who said Kofoed may appeal.
His conviction drew surprised gasps from the courtroom gallery on Tuesday, and Omaha's legal community was still abuzz a day later. Attorneys said the conviction undermined public confidence in the legal system and should lead to changes in the way many crime labs operate.
"When you have someone that is obviously cheating, there's nothing worse than that because the whole system collapses," said James Mowbray of the Nebraska Commission on Public Advocacy.
The Douglas County Sheriff's crime lab has tightened its investigation standards. It now uses testing kits better suited for single-use DNA collection and has reviewed some procedures to prevent accidental cross-contamination.
Omaha police Lt. Darci Tierney said there was no reason to think any of the cases Kofoed handled while working for their crime lab in the 1990s were tainted, but that if anything came up, it would be handled through the Douglas County Attorney's office.
Douglas County Attorney Don Kleine said his office reviewed several criminal cases after Kofoed was initially charged but found no other evidence of tampering.
Mock, who was once president of the Nebraska Criminal Defense Attorneys Association, said he expects many prisoners will now try to appeal, but that they'll have to have some factual arguments beyond the fact that Kofoed was involved.
It's rare for prosecutors to allege evidence tampering, but it does happen.
In Texas' Harris County, four prisoners' convictions were overturned because of faulty work by the Houston crime lab. A 2002 audit found that lab technicians were poorly trained, had misread data, and kept bad records. Authorities reviewed more than 150 cases involving blood-typing evidence from the lab.
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And this month, San Francisco prosecutors dismissed more than 250 drug cases because of accusations of evidence tampering in the city's crime lab. A longtime technician is accused of stealing cocaine evidence, although she hasn't been arrested or charged.