Hooper moved on. By late 1997, he was filling in at a Reno medical center operated by the U.S. Department of Veterans Affairs and tending to private medical laboratories he had opened in California, Nevada and Wyoming. (He eventually operated at least six, at various times.)
At the VA medical center, former co-workers remember him in rumpled khakis, singing along with Elvis recordings during autopsies or lamenting the ban on the diet drug combination fen-phen. He'd hurry through dissections and slides, then make phone calls related to his outside businesses, they say.
As at King/Drew, it wasn't long before the quality of his work came into question.
In May 1998, a surgeon discovered that Hooper had failed to notice one of two tumors in a section of colon she had taken out, according to VA documents that The Times obtained through the federal Freedom of Information Act. Another pathologist determined the growth to be cancerous.
After a second physician expressed worries, Hooper was found to have made at least two more serious errors, VA documents show.
Ultimately, hospital administrators opened an investigation and sent slides from 346 of Hooper's cases to the nationally renowned Armed Forces Institute of Pathology for a comprehensive review.
Of these cases, nearly a third contained mistakes. The institute found that Hooper had made major errors in 10 cases and minor errors in 104 more. Major errors typically require remedies such as chemotherapy or surgery.
According to a published study and two experts, the standard error rate for major mistakes by a general pathologist such as Hooper is less than 1% when all cases are reviewed.
Hooper's rate was nearly three times that.
His contract as a fill-in at the hospital was not renewed, VA officials said.
"I would not hire him ever" again, said Dr. Paul Jensen, former chief of pathology and laboratory medicine at the Reno facility. "Wouldn't even consider it."
But the VA kept Hooper's litany of mistakes to itself — never alerting the Nevada Board of Medical Examiners.
Dr. Thomas Barcia, the hospital chief of staff, said VA lawyers advised him that Hooper's errors fell within acceptable industry norms.
To this day, if another hospital called to inquire about Hooper, the VA would give him a clean reference, Barcia said, adding that "the data I have does not show he was a substandard pathologist."
In 1999, the year after the VA's investigation of Hooper, another arm of the federal government sanctioned him for lapses in his private Reno laboratory.
The Health Care Financing Administration determined that Hooper had falsely claimed the lab was accredited by the College of American Pathologists. In fact, he had never applied for such accreditation, government records say.
The regulators also found that Hooper closed the lab to avoid an inspection. The government banned him from owning or operating a pathology lab anywhere in the United States for two years.
Even before these sanctions, some associates had serious doubts about the quality of work at Hooper's labs.
One of them was James Champa, a Wyoming orthopedic surgeon and former medical school friend.