capacity
Legal Capacity of Children and Young People (Age of Legal Capacity (Scotland) Act 1991):
Children Under 16:
No contractual capacity generally, but exceptions for reasonable transactions (e.g., buying sweets, bus travel).
Young People Aged 16-17 (Special Protection)
Full contractual capacity unless the contract causes substantial prejudice.
Substantial prejudice means the contract would not have been entered by a prudent adult and harms the young person.
Intoxicated persons
X v BBC (2005) – (documentary) will be a judgement to what extent, if it is to such a degree that it renders them incapable of entering into legal obligations.
Third parties may also be affected if a contract is void, even if the third parties acted in good faith.
O’Neill v Chief Constable of Strathclyde (1994) – cannot acquire rights under void contract, one car was exchanged for another car but the car that was exchanged was stolen.
Seaton Brick & Tile Co V Mitchell, a contractor charged a client based on his own miscalculations but was held to be bound.
Wilkie v Hamilton Lodging-House LTD, a joinder offered to do work on reduced rates but miscalculated the amount which was obvious on the face of it and thus was entitled to change the amount.