Given the conditions and the fact his son wasnt wearing protective gear and is too young to have decided of his own free wheel to partake in such risks, I think that is fiar enough him getting sent down for it TBH.

Ive done far higher speeds than that on a bike with a pillion so im not anti biker or anti speeding, but Ive only ever done it with a consenting adult who knew what speeds I would be doing when they got on, never with a child on the back.