Spaccia was acquitted of one of two counts of hiding official records and jurors were unable to reach a verdict on one of six counts of misappropriation of public funds, KTLA-TV in Los Angeles reported.
An investigation into Bell's city government began in 2010 after the Los Angeles Times reported local officials in a city of about 35,000 were being paid extraordinary salaries. Spaccia was making more than $500,000 a year, while Robert Rizzo, the former city manager, was paid $1.8 million.
During the trial, Spaccia and her attorney argued Rizzo, who pleaded no contest in October to 69 counts, made the decisions. Rizzo has said Spaccia was the mastermind of the scheme.
Five City Council members charged with misappropriation of public funds were convicted in March.
Prosecutors say Rizzo faces at least a decade in prison, the Times said. His attorney told the newspaper he is likely to be ordered to pay up to $3.2 million in restitution.
Testimony ended in late November and the jury began deliberations the Friday before Thanksgiving. During discussions, they had to deal with thousands of pages of records.