• Video report by ITV News Business Editor Joel Hills

A month ago, in her manifesto, Theresa May pledged to abolish the Serious Fraud Office (SFO) if she won the General Election.

She is of the view that the SFO would do a better job fighting corruption and white-collar crime if it was folded into the National Crime Agency.

So SFO finds itself under intense scrutiny, more than ever there's a need to be sure-footed,this is a case it needs to win.

It's interesting that the Serious Fraud Office is pursuing legal action against Barclays at all, it could have settled out of court.

That's what the SFO did with Rolls Royce recently. The company agreed to pay an eye-popping fine to avoid a trial.

The question then is why wasn't a Deferred Prosecution Agreement (DPA) offered to Barclays?

One reason could be that that Barclay fought the SFO in court over access to 100,000 documents that the bank argued were legally privileged and confidential.

A DPA is only an option for companies that cooperate fully with SFO investigations.