In this shedinar, I look at the MCA and 16/17 year olds. This is a complicated area, so this can serve only as an overview. As I note in the video, the law in this area is evolving, and this represents the position as at the end of January 2021. I will seek to do an updated shedinar in due course to keep abreast of the position.
For a (much more) detailed discussion of some of the aspects of mental capacity and medical treatment, see this discussion paper. You may also want to watch this “in conversation” with Dr Camilla Parker which looks in much more detail at the concept of deprivation of liberty and 16/17 year olds.
Boring but necessary caveat: nothing in this constitutes legal advice.