If public protections in England against Covid-19 are removed for Christmas, is that lawful? Is it Gross Negligence Manslaughter? Is it murder?

As I write this early on 23rd November 2020, the media is full of stories that Boris Johnson is planning to remove or reduce public protections against Covid-19, in part so that the public in England can have a less abnormal Christmas. An announcement is expected in the House of Commons later today.

In this post I want to ask a basic question.

Is it lawful for Boris Johnson to remove or reduce public protections against Covid-19? 

Boris Johnson must know that removing or reducing public protections will result in an increase in Covid-19 infections. 

In turn, Boris Johnson must know that an increase in Covid-19 infections will cause an increase in Covid-19 deaths.

So, is it lawful for the Prime Minister to act in a way which he knows will cause deaths in the population of England?

If it's supposedly lawful, what is the reasoning that produces a conclusion that reducing public protections against Covid-19 with the effect of causing avoidable deaths is lawful?

If it's not lawful, what should it be called?

Might it be Gross Negligence Manslaughter?

Might it be Murder?