Director Charles Ferguson told Reuters TV on Thursday that criminal behavior on Wall Street is not prosecuted because politicians are scared of the financial sector's power.

Ferguson is the director of the 2010 Oscar-winning documentary Inside Job, which examines how banking practices, the housing boom, and deregulation led to the financial crisis. He is also the author of a new book, Predator Nation.

"In the four years since the crisis, there have been a number of private lawsuits and government investigations that have told us a considerable amount about what happened during the housing bubble and crisis," he explained, adding that much of what went on was "literally criminal."

Ferguson insisted that the crisis wasn't just a result of structural issues, criminal behavior played a major role.

"I think unfortunately we have reached a point in which the financial sector has enough political power that people in government either have been in various ways bought off -- literally or not -- or are afraid of going after criminal prosecutions."

Watch video, courtesy of Reuters, below: