There is no power for an LPA or Deputy, or for the parents of adults (over the age of 18), to consent to any deprivation of liberty.
Where this happens in a care home or hospital, the Deprivation of Liberty Safeguards (DOLS) provide external scrutiny and, if appropriate, authorisation, by the local authority subject to regular review. In other settings, including the patient’s own home, if the care package amounts to a deprivation of liberty for a patient who lacks capacity to consent to it then this can only be authorised by the Court of Protection.
However, following a judgment of the Court of Appeal in November 2017 (at least pending an expected appeal to the Supreme Court), special rules apply to young adults who are 16 or 17, and cannot make decisions about their own welfare for themselves. In certain circumstances, the consent of a person with parental responsibility can be relied upon as lawful authority for what might otherwise be a deprivation of the liberty, so long as giving consent to the situation falls within the ‘zone of parental responsibility’ – i.e. it is a decision that a parent can reasonably be expected to make. If there is any doubt about that, it may be worth referring to the local social services authority, who may in turn seek confirmation from the court.