Parent and Child: Jones v Padavatton [1969] 1 WLR 328
Husband and wife: Balfour v Balfour [1919] 2 KB 571
Merritt v Merrit [1970] 1 WLR 1211
Other social/domestic: Simpkins v Pays [1955] 1 WLR 975
Commercial Contracts: Esso Petroleum Ltd v Customs and Excise Commissioners [1976] 1 WLR
Note: Leonardo v Pepsico 88 F. Supp. 2d 116, (S.D.N.Y. 1999), American case -is it binding?
Capacity

Capacity relates to soundness of mind of a person's actions whereby that person has the capacity to enter into a legal relation under the same conditions as a person of sound mind or normal intelligence would have the power to enter.
The main categories refer to minors and people with mental incapacity.
Generally, a minor will not be bound by a contract. Fawcett v. Smethurst (1914) 84 LJKB 473, (Atkin J).
People suffering from mental disability or drunkenness when the contract is made may be seen to have mental incapacity. Gore v. Gibson (1845) 13 M & W 621; 153 ER 260