Richard Adkinson provides a quick guide to undue influence
Undue influence is an equitable species of fraud. In undue influence: “It is their weakness which is being protected not their inability to comprehend.”: See Lord Hobhouse in Etridge v Royal Bank of Scotland [2001] UKHL 44 at [111]. It covers almost any type of transaction. This includes a gift, loan, guarantee or other type of contract.
How is it established?
There are two routes to prove a plea of undue influence. It is ultimately a question of fact as to whether either route is made out.
Who must actually do the influencing? Constructive knowledge
Undue influence can be from the defendant or another. A claimant can establish undue influence if he can show the defendant had actual or constructive notice of the act of a third party or the defendant's agent. A defendant will be fixed with constructive knowledge unless he can prove he took sufficient steps to satisfy himself that the claimant's agreement had been properly obtained: Etridge at [34]–[43].
Route 1: Actual undue influence
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