"I am not a technical expert ..."
That rather sums up one of the main problems of parliament: people like Oliver Letwin who appear either not to have the capacity to understand the areas over which they have responsibility or to be intent on deceit as a means to further their agenda.
Checking out what he studied post-Eton - philosophy at Cambridge - a search brought up a speech he made this April to the UN.
His claim that the UK "is delivering a modern, balanced, evidence-based response to drugs within the UN conventions" is unconscionable. Professor David Nutt and his team were quite clear, before their forced retirement, about what a genuine evidence-based policy on recreational drugs should be.