Which document did you read?
"The underlying thrust of Cycling UK's comments (PDF, 5 pages) appeared to suggest that driverless vehicle technology in the UK should be banned in all circumstances except for operation on motorways. Their concerns stem from unspecified concerns over "immature, under-regulated technologies"."
No - the thrust is that you can't just ignore the criminal responsibility when you push insurance liability around.
If a person is unlawfully killed then there shouldn't be a way to just ignore the criminal responsibility - which current legislation doesn't transfer to the (corporate) authors of the software, but also cannot leave with a driver who isn't taking any action.