Mr Thant wrote:
[Interesting but ultimately irrelevent explanation deleted] and the user is charged a £4 unstarted journey
fee.

Is there any statutory basis for this penalty? The recent furore about
penalties for unauthorised overdrafts has brought up an important point
which is that consumer contracts essentially aren't allowed to contain
provisions that permit the service provider to 'fine' the consumer -
they can only charge the consumer the actual reasonable administrative
costs incurred as a result of the consumer's breach of contract.

Even assuming the byelaws provide a suitable statutory basis, if TfL
become aware that their system sometimes charges people this penalty
incorrectly, and they continue to levy the 'fine' with that knowledge,
it seems to me TfL would probably be acting illegally, perhaps even
fraudulently.

I suggest that Mizter T and Mr Thant communicate their observations
about the behaviour of the system to TfL, to ensure they can't rely on a
defense that they were unaware of this 'bug' in their software.

-roy