The best interest decision principle in the Mental Capacity Act 2005 states that any act or decision made on behalf of an adult lacking capacity must be in the individual’s best interests. This can cover financial, health and social care decisions. The individual making the decision is known as the decision-maker and is likely to be the person caring for or supporting the individual, the doctor or another member of the healthcare staff responsible for carrying out the particular treatment or procedure, or a lasting power of attorney (LPA) or Court of Protection deputy.
It is still important to involve the individual in the decision as much as possible, and try to find out what their views and wishes are, including those they had before they lost capacity to make the decision, and try to involve the individual in all meetings where decisions are being made about them.
Mae egwyddor penderfyniadau budd gorau Deddf Galluedd Meddyliol 2005 yn nodi bod yn rhaid i unrhyw weithred neu benderfyniad a wneir ar ran oedolyn â diffyg galluedd fod er budd gorau'r unigolyn. Gall hyn olygu penderfyniadau ariannol a phenderfyniadau mewn perthynas ag iechyd a gofal cymdeithasol. Gelwir y sawl sy'n gwneud y penderfyniad yn wneuthurwr penderfyniadau ac mae'n debygol mai hwn yw'r person sy'n gofalu am yr unigolyn neu'n ei gefnogi, y meddyg neu aelod arall o'r staff gofal iechyd sy'n gyfrifol am roi'r driniaeth benodol, neu atwrneiaeth arhosol neu ddirprwy'r Llys Gwarchod.
Mae'n dal i fod yn bwysig cynnwys yr unigolyn yn y penderfyniad cymaint â phosibl. Rhaid ceisio canfod beth yw ei farn a'i ddymuniadau, gan gynnwys y rhai oedd ganddo cyn iddo golli'r galluedd i wneud y penderfyniad, a cheisio cynnwys yr unigolyn ym mhob cyfarfod lle caiff penderfyniadau eu gwneud amdano.