The US federal law protecting corporate whistleblowers is failing to shield employees in the way that was intended, according to a non-profit group that is lobbying legislators for tougher rules.

The 2002 Sarbanes-Oxley Act, which contained new pro-whistleblower provisions when it was passed in the wake of the Enron and WorldCom scandals, “has helped few whistleblowers actually achieve justice”, according to the Government Accountability Project, an advocacy group that provides legal advice to whistleblowers.