When he is cross-examining 'Mr X', Rumpole points out that during the alleged blackmail Mr X paid the Lees by cheque, although his previous transactions with the Lees had always been in cash. Rumpole attempts to use this fact to establish that the blackmail accusation was false, claiming that Mr X deliberately paid by cheque to substantiate his blackmail allegation. However, even if Mr X did pay by cheque to provide evidence of the transaction, this does not prove that the blackmail accusation was false, all it proves is that Mr X wanted evidence of this transaction. Most people, if they were being blackmailed, would probably pay by cheque if possible so they would have a better chance of bringing their blackmailers to justice later on.