In P v Cheshire West, Lady Hale stated that an act that would deprive an able-bodied or able-minded person of their liberty would do the same to a mentally or physically disabled person. Throughout the judgement, there is no definition of what liberty is, which makes defining an act that would deprive a person of it difficult. Ideas of liberty are described in terms of political liberty within a society, the state of being free from external influence and individual autonomy. This essay explores various philosophical ideas of liberty and what a legitimate constraint of liberty is. It will be argued that defining liberty in terms external influence from other human agents undermines the impact of natural inability on a person’s ability to fulfil their intrinsic desires—a true constraint of liberty is any which prohibits a person from acting in the way they desire. If liberty is not the same for all, it follows that a deprivation of liberty differs between different agents. Although the government must protect personal liberty, it is important to recognise that an act that may deprive an able-bodied or minded person of their liberty, may in fact promote the liberty of a disabled persons. It will be argued that acts that allow a disabled person to act out desires that they ordinarily would not be able to perform, do not deprive them of their liberty.