47   Truth or falsity of imputation

On the question of the amount of damages where it is relevant to that question that the imputation complained of was or was not true or a matter of substantial truth:

(a)  there is no presumption as to whether the imputation was or was not true or a matter of substantial truth, and

(b)  evidence as to whether the imputation was or was not true or a matter of substantial truth may be adduced by any party (whether or not evidence on the subject is adduced by any other party).