That last bit is interesting since I would have thought riding a bike with an illegally powered motor, that then resulted in death, might qualify as killing someone while carrying out a criminal act - which is more or less what manslaughter means. Perhaps the illegal motor does not reach the level of 'criminal act'. Maybe it is regarded as some sort of minor misdemeanour.
His bike did not have an illegally powered motor in law, he was riding a motorcycle in breach of the Two and Three Wheeled Type Approval regulation 168/2013. That contains an exemption from being a motor vehicle providing certain conditions are met, in the case of bicycles the conditions including the 250 Watt limit.
Any vehicle failing to meet an exemption standard is automatically a motor vehicle requiring registration etc.
So he could have been charged with a number of regulation breaches, no tax, no insurance, no registration and number plate, no motor cycle approved helmet etc., etc. But there was the more serious issue of death to be considered.
So no doubt, as in other similar cases, he was charged on the basis of riding a bicycle, the breach of 168/2013 and its implications ignored and only the cycling liability tried on the basis that the woman who suddenly ran into his path gave him no chance of stopping.
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