The tremendous advances in telecommunications have made it easier to know where the money is. They may not be able to predict how the price of money will rise or fall. And they can't control the ups and downs of the capitalist market. But they do know where all the money is. Generally the big banks have little to fear from government investigations.
Convictions are minimal and considered laughable.
The government doesn't want to show the real source of the drug traffic. They will accuse some underlings, some minor figures, but they do not want to point out the real center of it-the big banks and the Federal Reserve system itself. Banks investigated in 1986 The Reagan administration and the banks got off easy in 1986. The Treasury department had been investigating the laundering of money by the big banks. It could have been an enormous scandal showing a corrupt criminal conspiracy between the banks and the drug dealers.