Banks face rising regulatory costs in monitoring customer accounts for money laundering and other financial crimes. But banks also are supporting better law enforcement in their industry as government agencies tap into growing electronic archives of suspicious account activity.

"The art of account monitoring is far more advanced now than it was 10 years ago," so regulators are pushing banks to keep up with improvements in technologies and methodologies, said Rick MacNamara, director of anti-money laundering at the Miami branch of the Federal Reserve Bank of Atlanta.