Final answer:
A capable relative can make medical decisions for an incapacitated individual unless the person had previously expressed different wishes, as in a living will or advance directive. The designated health care proxy can override family decisions if appointed.
Step-by-step explanation:
The subject in question relates to the decision-making rights regarding medical treatment when an individual is incapable of making decisions for themselves. According to both medical ethics and legal standards, a spouse, partner, or relative who is present when the treatment is proposed may make decisions, unless the incapable person expresses a contrary wish, which is to say, if the person has previously made clear their wishes about their healthcare decisions, those expressed wishes must be honored. This is typically documented in a living will or advance directive. Such documents can include a health care proxy, which appoints a specific person to make medical decisions on behalf of the patient, or a Do Not Resuscitate (DNR) Order. Decisions made by family members may also be subject to age and legal relationship constraints, such as being legally married or being of legal consenting age. Other considerations, like whether the decision-maker disagrees with the proposed treatment, can further complicate the decision-making process.