Life for Josiah Sutton when he left prison was as uncertain as the evidence that convicted him. Sutton spent the heart of his teenage life in prison for a rape he didn't commit after the culmination of sloppy lab work and negligence by the Houston Police Department (HPD) Crime Laboratory and his defense team.
Sutton could have easily been exonerated with a simple DNA test of an evidence sample. Four years after his conviction, he finally was. At age 21, Sutton walked out of prison in 2003.
The Sutton case was one of more than 3,500 cases processed by the HPD Crime Lab dating back to 1980 that were reviewed by independent investigators after major problems were exposed in late 2002.
The reviews found hundreds of cases where incompetence, inadequate training and resources, lack of guidance and even intentional bias on the part of a crime lab - which is not independent from the HPD - contributed to mistakes.
"It's really a complicated issue not just for this crime lab. With this crime lab, almost everything that could go wrong did go wrong," said Marie Munier, chief of the Public Service Bureau with the Harris County District Attorney's Office, which prosecuted Sutton and others whose cases are still being examined to determine the extent of mistakes and whether they led to wrongful convictions.
Some problems with the HPD Crime Lab - such as underfunding, poor staff training and close ties to police and prosecutors - also may be inherent in crime labs across the country.
A 2004 investigation by the Seattle Post-Intelligencer found 23 DNA testing errors in serious criminal cases handled in a Washington state lab. In North Carolina, the Winston-Salem Journal recently ran a series of articles about many DNA testing errors by the North Carolina State Bureau of Investigation. In Virginia, it took an outside investigation to clear Earl Washington Jr., who was falsely convicted of capital murder and nearly executed. An independent lab reused the same samples that led to his conviction but found contradicting results.
That's not all. DNA testing errors are cropping up nationwide: California, Minnesota, Pennsylvania and Nevada have documented major problems recently.
Munier agreed the troubles are widespread. These issues have prompted critics to call for greater independence among the nation's crime labs, which typically are run by law enforcement agencies.
In Houston, chronic problems with forensic evidence produced by the crime lab resulted in new independent oversight and accreditation of the facility, as well as increased investment in staff salaries, equipment and training.
"One of the most critical parts of a lab is to have outside scrutiny, and that was not occurring," said Irma Rios, the new director of the Houston lab. The facility now undergoes external and internal audits; proficiency testing and competency testing of the examiners; retesting of completed cases; blind sample testing; testimony monitoring, and internal and external training.
In addition, the lab installed cameras and limited access to personnel with card readers. "We're implementing a laboratory information system where there's a lot of traceability of people," Rios said. "Those are some of the things we've done to increase the monitoring."
In late 2002, television station KHOU in Houston looked into deficiencies of the HPD Crime Lab and asked William Thompson, University of California, Irvine professor and forensic expert, to investigate.
"The problems were just obvious," Thompson said. "They weren't running proper scientific controls. They were giving misleading testimony. They were computing their statistics incorrectly - in a way that was biased against the accused in many cases."
In some cases, Thompson found simple errors where documentation said Sample A matched Sample B, for instance, which was untrue. There were cases where Thompson found inconsistencies between the lab report and what