A high-level investigation into the fake accounts scandal at Wells Fargo blamed a "sales-oriented culture or a decentralized corporate structure" that "unfortunately coalesced and failed dramatically," resulting in one of the worst banking controversies in years.

A report obtained by CNBC detailed the findings of the investigation, which was overseen by a special board committee chaired by Stephen Sanger and including three other independent directors: Elizabeth Duke, Enrique Hernandez and Donald James. To assist the special committee, the group retained law firm Shearman & Sterling.

The investigation included 100 interviews of current and former employees, reviewed information concerning more than 1,000 existing and past investigations, and searched more than 35 million documents.

The review was particularly critical of the former head of Wells Fargo's community bank unit, Carrie Tolstedt, and the way she and her team allegedly cultivated a culture that led to wrongdoing:

"Even when challenged by their regional leaders, the senior leadership of the Community Bank failed to appreciate or accept that their sales goals were too high and becoming increasingly untenable." "It was convenient instead to blame the problem of low quality and unauthorized accounts and other employee misconduct on individual wrongdoers." "Effect was confused with cause. When Wells Fargo did identify misconduct, its solution generally was to terminate the offending employee without considering causes for the offending conduct or determining whether there were responsible individuals who, while they might not have directed the specific misconduct, contributed to the environment that increased the chances of its occurrence."

Tolstedt did not respond to a CNBC request for comment, but Reuters quoted attorneys for the former executive as saying "we strongly disagree with the report and its attempt to lay blame with Ms. Tolstedt." A full examination of the facts will produce "a different conclusion," the attorneys said.

The report provided detailed examples of how this culture manifested.