Fujioka said the information was discovered after the county ordered fingerprints from all 1,600 employees working at Martin Luther King Jr.-Harbor hospital when it closed inpatient services nearly a year ago.
The California Department of Justice returned with information that some employees had previously undisclosed criminal histories. But the county's Human Resources Department did not take appropriate disciplinary action against them, Fujioka said.
"I have considerable concerns over what has happened," he said.
He declined to say how many employees were involved or what criminal offenses were found, though he said more information might be revealed today after he consults county attorneys.
Some of the convictions are serious enough to prompt immediate disciplinary action against the employees, including termination, Fujioka said.
County job candidates are required to disclose any criminal convictions on their job applications, and employees face dismissal if they conceal criminal records. Those convicted of crimes while employed by the county have their records evaluated for possible discipline or dismissal.
Additionally, eight or nine employees have refused to provide their fingerprints for a criminal background check, according to a senior manager who asked The Times for anonymity because he was not authorized to disclose the information.
"It is unacceptable for any of our employees to refuse," Fujioka said. "Such a decision will be considered insubordination and will be disciplined."
The lapse in the county's response to the criminal information was discovered in recent days after the Board of Supervisors ordered a thorough review of problem employees from King-Harbor.
The review was in response to a report in The Times that the county had failed to fully track employees who had been disciplined by their managers.
Fujioka said the county would also try to identify the workers who failed to initiate action against the convicted employees for probable disciplinary action.
The department discovered last week that the information about the employees had been neglected, but county officials were initially reluctant to reveal the problem, despite the supervisors' request to quickly disclose bad news.
"I think the whole culture of reticence to be open about things and to try to avoid bad news or avoid delivering bad news up the chain of command is extremely unhealthy," Supervisor Zev Yaroslavsky said last week.
County Department of Health Services interim director John Schunhoff sent a memo Friday providing an overview of what the department had done to review problem employees. But the memo made no mention of the criminal history discovery.
In response to questions about employee criminal histories Monday, Health Services Department spokesmen Michael Wilson and Rene Seidel said the department was still investigating and could not reveal results. Fujioka revealed the findings Monday when reached by The Times.
Tony Bell, a spokesman for Supervisor Mike Antonovich, said his office had asked repeatedly in recent months for a status report on the criminal histories of King employees.
"We are finding that there has been some deliberate misinformation given to the board," Bell said. "The revelations about the employees' criminal histories is just one more chapter in this hospital's deplorable story."
Federal regulators forced the closing of emergency and inpatient services after they found that the hospital near Watts had failed to meet minimum standards for patient care. At the time, county supervisors vowed to "wipe the slate clean" of problem employees."
Times staff writer Jack Leonard contributed to this report.