Lester left the State Police but was later rehired.
Castelle told U.S. senators that West Virginia's system of having crime labs under the control of the State Police, and not in a neutral scientific setting, is a fundamental flaw in the system.
"I get the sense that there's been numerous improvements in the crime lab but it's not possible to confirm because there's not open independent oversight," Castelle told the Gazette this month.
Sen. Dan Foster, D-Kanawha, said some state lawmakers have discussed changing the way some tests are handled. Some of the State Police forensic lab's duties would be taken over by West Virginia University or Marshall University.
"There was some support of at least expanding those opportunities because of the belief that there's been delays in getting work done in specific criminal cases," Foster said.
Throwing out Zain's tests didn't end the lab's problems. In 2000 lab worker Todd Owen McDaniel pleaded guilty to mail fraud charges after admitting he cut corners on drug tests at the lab in 1993.
"It's troubling, it raises questions even today," Castelle said. "There is something fundamental in the nature of science, true science, that is open and reviewable - it's repeatable.
"We hear claims of increased professionalism in law enforcement agencies, and I hope the claims are right," he said. "Without civilian oversight or public disclosure of investigations, the progress can't be confirmed."
Reach Gary Harki at gha...@wvgazette.com or 304-348-5163.