As this is being written, I am reading (yes, multi-tasking, me) all about the technical problems NatWest has had on its wonky-banky computers. All manner of glitches have appeared. Twitter almost tweeted itself to death (which would be a benefit, I suppose). So, as if we didn’t know, really big organisations can have computer glitches.

Brings me neatly to the Post Office and its Horizon computer accounting system. Some readers will recall that I have reported many claims that the Horizon system has glitches - always denied by the PO. There have been bankrupted and even imprisoned sub postmasters/mistresses who felt impelled to falsify their accounts to cover for unimaginable amounts of missing money (average £35K) according to the ‘infallible’ Horizon system.

At the same time that NatWest made its announcement, the PO announced that it had appointed external investigators to examine allegations of deficiencies in the Horizon computer system used in all its outlets.

The PO has instructed a firm of forensic accountants, 2nd Sight, to conduct an independent review of 10 existing cases raised by MPs and the law firm Shoosmiths (which is actually acting on behalf of dozens of retailers).

So far, so good.

But I think I agree with Conservative MP Andrew Bridgen (lots of MPs have been involved in these cases) when he says: “I would far rather they be appointed by another body. I would prefer it if they were paid by the Cabinet Office.”

Hear, hear.

And Lee Castleton, who lost his business over Horizon, points out that forensic accounts isn’t what is needed.

“Forensic IT specialists is the requirement here. Why would you appoint an accounts specialist when the system, including crown offices, is losing transactions? It’s the nuts and bolts of the programming that is at fault! The post office already knows that the accounts in general will add up because they have looked previously. It’s the IT that is losing transactions that is causing the problem, not the accounts. The system can only add and take away what it can see.”

He sent me some paperwork that shows a parcel being transacted and then a list of all transactions that shows the parcel was never transacted, and he asks: “How will a forensic accountant find something that the system thinks never happened?”

Indeed, the document shows a receipt for the parcel, but it is missing from the transaction log.

“The big problem with this is the customer would walk out of the door with the receipt and the parcel would have been the only other proof that the physical transaction had taken place, attached to it in the form of the post label (printed stamp). How the heck is all that information going to be available to the forensic accountant?”