Who is in charge of decision making at a home birth?

I've been wondering why there is no indemnity insurance for independent midwives, and how the Nursing and Midwifery Council could provide better support.

Clearly there are issues of responsibility in home birth, when much responsibility for decision-making devolves to parents, rather than hospital consultants, and even the midwife in attendance may bow to parents’ wishes, or at least some of them. The professional body responsible, the Council of Nursing and Midwifery should have confronted these issues years ago, when indemnity insurance became prohibitively expensive in 2004.

It seems to me, from my lay-person's perspective, that is needed is a professional information and disclaimer document that forms an agreement between parents and midwives, which outlines the risks, and gets parents to make key decisions before birth. That might enable insurance rates to be worked out. It is obviously hard for independent midwives working in isolation to devise such an important document.