The allegations this week against London-based Standard Chartered Bank raise questions, not just about the bank's viability but also about the efficacy of U.S. laws when it comes to foreign banks. Standard Chartered allegedly violated U.S. sanctions against Iran, and regulators said the bank's executives lied to investigators as part of a cover-up.

The case serves as yet another reminder that U.S. regulations, which have strengthened since the Sept. 11, 2001, terrorist attacks, apparently did not deter foreign banks from laundering money through their U.S. operations.

Standard Chartered enjoyed a sterling reputation until this week, when the New York Department of Financial Services charged it with laundering $250 billion of Iranian funds through the bank's U.S. division. But now Standard Chartered is among legions of non-U.S. banks that have been charged with, or settled, similar allegations.

"The rules are on the books that make it more and more difficult," says Jeffrey Neiman, a former federal prosecutor turned defense attorney based in Fort Lauderdale, Fla. "But the bottom line is you can have all the laws in the world — if people want to launder money, there's always going to be people who can find a way to launder money."

'The Big Elephant In The Room'

What is remarkable about the charges against Standard Chartered, experts say, is the extent of its efforts to carry out a huge number of transactions over nearly a decade, starting in 2001.

The case brought by the New York regulator reads like a true crime novel. The bank allegedly set up an elaborate system to send electronic payments through its U.S. division, to and from Iranian banks. To disguise these payments, Standard Chartered stripped or falsified data in wire transfers.

The case also cites emails in which bank executives fret about getting caught. They allegedly colluded with consultant Deloitte & Touche to mask violations.

In 2010, the bank had given both state and federal regulators data and documents about its transactions. But according to a source, the information was not investigated until earlier this year. Now the Justice Department and FBI, among others, are also investigating possible criminal wrongdoing. According to the source, the parties are also in the early stages of negotiating a possible settlement deal with the bank.

What concerns money-laundering experts is how foreign banks seem to have a general disregard for U.S. regulations, which are designed to monitor and restrict funds that may flow to drug or terrorist groups.

"The big elephant in the room is that banks outside the U.S. during a global financial crisis find it very tempting to have very profitable business relationships with banks or potentially sanctioned entities or other high-risk individuals that the U.S. government would prefer they not do business with," says David Stewart, who directs the financial crimes division for SAS Financial Services, a technology company that helps banks and regulators prevent fraud.

Such transactions are subject to rules set by the Treasury Department's Office of Foreign Assets Control, also known as OFAC. But Stewart says OFAC and its rules often meet with ridicule.

"I was just at an Asian bank and a gentleman who was over compliance jokingly said, 'We hate you Americans because of OFAC.' And he was only half-joking," Stewart says.

The Electronic Crime Scene

The charges come after six other European banks have settled or are accused of laundering money, including, most recently, British bank HSBC.

Standard Chartered declined an interview but in a statement said it strongly rejects the portrayal of facts in the case. It says most of its transactions relating to Iran complied with regulations. Deloitte & Touche denied knowledge of misconduct, saying, it "categorically denies that it aided in any way any violation of law by the bank."

Charles Intriago, president of the Association of Certified Financial Crime Specialists, says that the charges against Standard Chartered illustrate how the U.S. laws — which were strengthened in 2008 — have not made it much harder to launder money.

"It's not difficult. There are so many ways to disguise the flow of money," he says.

Of course, every transaction also leaves a kind of digital footprint that is nearly impossible to erase, which helps investigators. So-called e-discovery technology has also made it much easier for investigators to sift through reams of transactions much more quickly.

Still, Standard Chartered's worst enemy, Intriago says, are the emails executives exchanged acknowledging their deception. He says he doesn't think it's possible to interpret them in more than one way.

'Environment Of Impunity'

Jimmy Gurule, a University of Notre Dame law professor and former Treasury undersecretary who oversaw OFAC, notes that when the bankers themselves — instead of, say, individual drug dealers or terrorists — are engaged in the money-laundering, they're harder to catch. They must circumvent their own internal controls, but they also have the know-how to get around them, he says.

"If it's the banks that are the persons that are involved in the money-laundering and the corruption, yeah, it's going to be harder to detect," says Gurule, who worries that enforcement measures have been too weak.

Standard Chartered faces state regulators next week and could get hit with penalties and possibly the loss of its license to operate in the U.S. But, Gurule says, "Why is there reason to believe that other banks, to one extent or another, are not involved in this?"

Gurule argues that if bank executives were criminally charged and jailed for such offenses, it would be an effective deterrent. But so far, none of the money-laundering cases in recent years have put anyone behind bars.

"We've seen a pattern here of this, I think, rather deferential treatment given to the bank, and the bank officials," he says, "and I think it's created this environment of impunity. I think these bank officials [say], 'Hey, why not?' "

Neiman, the former prosecutor, says the reason it's so hard to punish a bank is that other factors must be weighed.

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