It is far more normal in the statute book for offences to be strict liability. You see very few absolute liability offences. And so in this context the absolute liability of the operator, in the event of an accident, is quite exceptional in the rest of the bill, and it was thought necessary to make it clear that when we get to clause 65, we're back in the normal world of due diligence and strict liability.
On December 6th, 2007. See this statement in context.