The largest credit union fraud cases of 2016 convicted two CEOs, a CFO, a bookkeeper, a business relationship manager, and an assistant manager who collectively stole more than $66 million from their credit unions. And they got away with it for years before their fraudulent schemes were finally uncovered.

In last year's biggest embezzlement case, the $1 billion Scott Credit Union in Edwardsville, Ill., suffered $25.8 million in criminal and civil losses because of the criminal action taken by Theodore J. Longust, a former business relationship manager, who was sentenced to 10 years in prison in November.

For six years, Longust falsified reports, created unauthorized loans, loan advances, and concealed his fraud by falsifying reports, misstating loan balances, omitting loan amounts and underreporting loans.