A jury found 43-year-old Tyrone Freeman guilty of 14 counts including embezzlement, mail fraud and theft of labor union assets, false statements and tax fraud charges Monday.
Freeman was president of the Service Employees International Union and represented 180,000 low-wage healthcare workers between 2006 and 2008.
The ex-labor chief reportedly diverted reimbursed payments from a public-sector union that had close ties to the healthcare workers group.
According to federal prosecutors, Freeman secretly collected $25,000 per month from the California United Homecare Workers during an 18-month period. He also billed expenses from a trip to Honolulu and his wedding on a union credit card.
"This was a case about abuse and betrayal," U.S. Attorney Andre Birotte Jr. said. "Freeman abused his position as leader of the SEIU, and he betrayed the hardworking people whose interests he was supposed to represent."
Freeman is scheduled to be sentenced in April. His wife pleaded guilty in June to a misdemeanor income tax charge in connection with more than $540,000 she received in consulting payments.
CNS contributed to this report.