A recent suggestion of some disability legal scholars is to provide a non-discriminatory legal framework to regulate non-consensual medical and care interventions in relation to disabled people through adapting the doctrine of necessity. This article rejects this approach through a close reading of the leading decision on the doctrine of necessity in medical and care settings, In re F (Mental Patient: Sterilization)  2 AC 1. This decision confirms that any such suggestion for the application of the doctrine will impact disabled people differentially due to divergent legal constructions of temporality between disabled and able people. To use this doctrine in relation to ongoing disabled medical and care interventions the law constructs disabled people as being in a permanent state of mental incapacity. On the other hand, the doctrine of necessity constructs able people as temporarily mentally incapacitated from their usual state of autonomy, thus only requiring minimal medical and care interventions to return them to their prior state. Therefore, able people cannot, under this doctrine, lawfully be subject to similarly long periods of intervention and such a broader range of interventions. Application of the doctrine of necessity will thus exacerbate inequality of and violence against disabled people.