The illegality defence is governed by a trio of policy considerations rather than the reliance test, requiring courts to weigh the purpose of the relevant rule, public policy, and proportionality.
Contract — Frustration and Illegality
Illegality defence requires sufficient connection between the turpitude and the claim; mere incidental illegality will not bar recovery.
A contract is frustrated only where a supervening event renders performance radically different from what was originally contemplated by the parties.
A contract is discharged by frustration where supervening impossibility, not caused by either party, renders performance fundamentally different from that undertaken.
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