US Department of Justice
The US Department of Justice has been taking a harder line against banks that break the law (Reuters)

Banks that continue to offend despite being under scrutiny can expect the full measure of US law, the deputy chief of the Justice Department has said.

James Cole, deputy attorney general at the Justice Department, said banks that repeatedly break the law would be punished, during an anti-money laundering conference in Washington.

"When we see repeat players such as banks that previously entered into non-prosecution agreements or deferred prosecution agreements, and yet are under scrutiny again for other violations, we will have no choice but to consider all of the possible actions at our disposal," said Cole

When banks uncover one problem the government expects them to thoroughly review other offices and business units to seek out similar problems in other areas, said Cole.

"We've seen this pattern at a number of financial institutions.

"What it tells us is that even if the specific conduct didn't directly involve senior management, the repetition speaks volumes about the culture senior management has created.

"When we see criminal violations in multiple business units or locations, we will hold banks accountable," he said.

The Justice Department has come under fire in recent years for the lack of big cases against Wall Street executives, specifically in relation to the 2007-2009 financial crisis.

It has since brought a steady stream of cases against financial institutions over Libor manipulation.

Many of the world's leading banks have already been fined for being involved in a variety of scandals including fixing the London Interbank Offered Rate (Libor) or manipulating currencies in the foreign exchange markets.

The Justice Department acknowledged publicly for the first time late last month that it has an "active ongoing investigation" into foreign-exchange rate manipulation.

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