In one of the area's largest-ever cases of employee theft, an accounting manager for Cargill at the Port of Albany admitted Monday she stole more than $3.1 million from the global agriculture giant over 10 years. Backis pleaded guilty to charges of mail fraud and filing a false tax return, which under federal sentencing guidelines could send her to prison for more than 11 years. "The defendant was not, and knew she was not, authorized to deposit Cargill customer payments into her personal accounts or use Cargill customer payments for personal expenditures," Assistant U.S.