The Colorado health department has announced changes at its toxicology lab after an investigation found that a refrigerator holding blood-alcohol samples from suspected drunken drivers was unlocked.
The investigation also found inadequate staff training and understaffing.
The Colorado Department of Public Health and Environment says all refrigerators with blood-alcohol samples are now locked and the staff is receiving more training.
Department head Chris Urbina says the investigation was launched following staff complaints about a supervisor, who retired last week.
Colorado Attorney General John Suthers advised attorneys in a letter Friday that a report on the investigation included information that could be mitigating evidence in the prosecution of certain cases involving the lab.
Urbina and Suthers' office stress that the investigation concerned personnel issues, not the validity of the lab's tests.