Paul,
I think I recall the incident you are referring to. It happened around 1990/1 in SE England, the home owner's grandson was electrocuted as a result of the electrician's negligence. Electrician was jailed for manslaughter.
If my memory of the account given in the trade press is correct, the scenario was this:
Electrician wired central heating boiler & controls using 3 core flexes instead of 4 or 5 core flex. He used a green/yellow core as a switched phase (against regs.) at one end and connected the other end to the earth terminal of a piece equipment.
Electrician was called out (at least twice) to investigate people getting shocks from the sink, and failed to identify the fault, perhaps because it was only energized when the programmer was in "heating on" mode.
A failure of 2 safety devices, a faulty MCB in the consumer unit & lack of adequate earth bonding to water pipes, resulted in the sink becoming live at 240V.
I don't recall any mention of reverse polarity at the meter or mains board.
It was a clear case of incompetence & bad workmanship by the "electrician" and the jury recognised this.
