The US Justice Department said on Thursday that it won't prosecute Wall Street firm Goldman Sachs over financial fraud.
The department said it had conducted an exhaustive investigation of allegations brought to light by a Senate panel investigating the 2008-2009 financial crisis.
"The department ... ultimately concluded that the burden of proof to bring a criminal case could not be met based on the law and facts as they exist at this time," it said.
A Senate subcommittee in 2011 found that Goldman marketed mortgage securities to banks and other investors but failed to tell clients that the securities were very risky.
The Senate panel said Goldman secretly bet against the investors' positions and deceived the investors about its own positions to shift risk from its balance sheet to theirs.
The decision capped a good day for the speculators as the Securities and Exchange Commission also decided not to file charges over a $1.3 billion (£800 million) subprime mortgage portfolio.
As Aslef's annual assembly of delegates begins in Edinburgh tomorrow the general secretary explains the challenges his members - and workers across the country - face