Excuses
Excuses: Facts Change
Impossibility will excuse a party from performing where a change in facts makes performance actually or legally impossible. (illegallity, death of particular person)
Impracticability will excuse a party from performing where performance is rendered impracticable due to the occurance of an unforseeable event, the non-happening of which is a basic assumption of the contract. (more expensive or inconvenient is not enough)
Frustration of purpose will excuse a party from performance where circumstances arise that substantially frustrate a party’s purpose; provided that the event was reasonably unforseeable and the purpose is destroyed or nearly destoryed.
Excuses: Change in Agreement
A party can be excused from performance where a valid subsequent agreement of the parties relieves the party of the duty to perform.