Can my Health and Welfare attorney refuse medical treatment on my behalf?

Only if you've specifically given them that power in section 5 of the LP1H. By default, Health and Welfare attorneys can make decisions about most care and treatment, but they cannot refuse life-sustaining treatment unless you've ticked the box on the form giving them that authority. If you don't tick that box, decisions about life-sustaining treatment fall to doctors acting in your best interests (or to an Advance Decision document you've made separately). This is one of the most important decisions in the whole form and people often tick it without thinking. We always walk you through it before you sign.