According to a former top official from the Federal Bureau of Investigation who was involved in investigating firms for wrongdoing connected to the financial crisis, the agency's probing of mortgage lenders and securities firms has turned up little fodder for criminal charges.

The official, David Cardona, said that many of the cases which the FBI hoped would give rise to criminal charges, including fraud, may actually be best pursued on the basis of civil charges.

Early optimism about the probes has apparently given way to the realization that much financial wrongdoing cannot be effectively pursued as criminal charges, particularly because of difficulties in proving criminal intent. In particular, the issue of disclosure has been a central one. It isn't always easy to determine whether there has been adequate disclosure, and federal prosecutors have also been hesitant to submit question of disclosure to juries.

Currently, the FBI is still investigation over 2,800 mortgage-fraud cases, but nowadays the Justice Department is doing more deliberate targeting of cases before criminal investigations are launched.

The Securities and Exchange Commission continues active investigations into such cases, and has already filed civil-fraud cases against 81 firms and individual and negotiated almost $2 billion in settlements.

Source: Wall Street Journal, "Financial Crimes Bedevil Prosecutors," Jean Eaglesham, December 6, 2011.