Bankers involved in the Libor-rigging scandal could face jail terms after the Serious Fraud Office (SFO) confirmed that existing legislation will suffice to bring criminal actions against banks and individuals.

In a statement, the SFO said: "The Director of the Serious Fraud Office, David Green QC, is satisfied that existing criminal offences are capable of covering conduct in relation to the alleged manipulation of Libor and related interest rates. The investigation, announced on 6 July, involves a number of financial institutions."

The SFO announced a formal investigation into the scandal earlier this month, after Chancellor George Osborne confirmed that the Financial Services Authority (FSA) was not able to impose criminal sanctions for the manipulation of Libor.

Although no specific banks are named in the statement, one former SFO official told Legal Week that Barclays, the Royal Bank of Scotland and Lloyds Banking Group – which are already the subject of a number of separate investigations – are among the institutions that could be inspected.

The latest announcement provides clarity after recent debate as to whether the Fraud Act of 2006 would provide a sufficient foundation for the anti-fraud body to bring charges against financial institutions and individual bankers.

A separate Libor enquiry by the FSA is expected to feed into the SFO's investigation, with FSA enforcement and financial crime director Tracey McDermott leading the team.

So far, Barclays is the only bank to have agreed a settlement with US and UK regulators, with the bank last month agreeing to pay around $450m (£290m) to settle charges that it attempted to manipulate interest rates and made false reports to benefit its derivatives trading positions.

Meanwhile, Barclays is among a group of 21 banks including Bank of America and Citigroup currently facing a new lawsuit from New York's Berkshire Bank over the alleged manipulation of Libor.

Berkshire's lawyers at US litigation firm Pomerantz Haudek Grossman & Gross have filed a complaint on behalf of all New York financial institutions that "originated, purchased outright or purchased a participation in" loans paying interest rates pegged to Libor, seeking compensatory damages.

Separately, the High Court has today ruled that search warrants issued to the SFO in its investigation into businessmen Robert and Vincent were unlawful, as they were "obtained by misrepresentation and non-disclosure to the judge".

Robert Tchenguiz is now set to pursue the SFO for damages for the impact that the investigation has had on his business and reputation, with Stephenson Harwood in the lead role. The firm has also been acting for Rawlinson & Hunter, the trustees of the Tchenguiz Family Trust.

Commercial litigation partner Sean Jeffrey commented: "This case will be the cause of changes that will go a long way to ensure that thorough and proper steps are taken before permission is given for a dawn raid in the future and that such raids are executed properly."

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