Horizon expert ‘gave evidence based on informal chats’

At the inquiry on Wednesday, lead counsel Jason Beer asked Mr Jenkins a series of questions about how much he knew about Fujitsu’s ability to remotely access sub-postmaster computers.

In its prosecutions, the Post Office had argued that Horizon could not be accessed remotely by any other party.

This showed that accused subpostmasters must have been responsible for the shortfalls in their accounts, it said.

But this turned out to be untrue, depriving those accused of an important line of defence.

Remote access was not only possible by Fujitsu’s engineers, it could be done without leaving any trace, in a way that was indistinguishable from changes made by subpostmasters.

Mr Jenkins told Mr Beer he had only found this out in 2018.