Medical exams are voluntarily (sometimes not in the cause of a trauma, or where a patient is psychotic or something and a consent override has been obtained, bu

Medical exams are voluntarily (sometimes not in the cause of a trauma, or where a patient is psychotic or something and a consent override has been obtained, but we already have legal protection for these cases) - if a person refuses to let a MD look at their legs because their spouse was beating them with a bat then they can do that. Asking questions, however, doesn't require a warrant - even for a government employee. Once a MD sees bruises they are free to probe (and it's partially so they can treat other damage that may not be visible on the surface) into how they got there.