Non-consensual physical contact forms the basis of the criminal offence of assault and the civil wrong of battery; laws which affirm principles that seek to ensure preservation of individual integrity and the inviolability of the body.
In addition to legitimising otherwise illegal acts of contact, consent, as a reflection of choice, lies behind ethical notions of individual autonomy and self-determination.
A respect for these principles should form the basis of good medical practise, rather than outdated ideas of medical paternalism exemplified by the maxim ‘doctor knows best’, which often resulted in the relegation of therapeutic consent to paper exercises.
Whether an individual is able to give consent, and whether indeed such consent is ‘true’ or legally valid is dependant on three factors. The individual must have sufficient capacity, they must possess sufficient understanding or knowledge of the proposed intervention, and their agreement to undergo the proposed treatment must be voluntary, that is, it must be freely given and not tainted by any degree of coercion or undue influence, either from the healthcare professional or family members.
There is a legal presumption that any person over the age of 18 who is not suffering from a mental incapacity (infra) is capable of giving consent for, or refusing, medical treatment, unless there is evidence to the contrary.