The great day has arrived. The Mental Capacity Act 2005 is now in effect.
Though I'm not sure how many people who take out an LPA are aware that the withdrawal of "treatment" includes denying water, so patients in hospital can be made to die slowly of thirst ("Since a landmark House of Lords judgment in 1993, providing food and water to those who cannot eat or drink for themselves counts as treatment as well."). And no-one can be certain what is felt by someone who is apparently in a coma.
Doesn't this conflict with the Hippocratic Oath?
What oath? Wikipedia says:
In the 1970s, cultural and social forces induced many American medical schools to abandon the Hippocratic Oath as part of graduation ceremonies, usually substituting a version modified to something considered more politically up to date, or an alternate pledge like the Oath or Prayer of Maimonides.
A Catholic scholar details the Oath and its history here.
The Act is here; the government's own take on it is here.
We seem to be approaching a time when anybody except a criminal may be lawfully killed.