“… not consider that, in the event of the conviction being referred, even if the Court of Appeal were minded to adopt a “flexible approach” about collateral evidence in the case, it would have any bearing on the outcome. The fresh evidence from the corruption investigation report, namely information about how and when Mr Edwards took up his employment with FIA and what remuneration he received, does not relate in any way to how the court would regard the Bostons’ remarks to Mr Nathanson in the tape recorded conversations. Nothing in the Report impacts upon Mr Nathanson’s evidence about those conversations. Nothing in the Report touches on issues that would render the convictions unsafe.”
“Before we come to answering the questions posed we think it necessary to go back to first principles. One starts with the obvious proposition that in a trial relevant evidence should be admitted and irrelevant evidence excluded. “Relevant” means relevant according to the ordinary common law rules of evidence and relevant to the case as it is being put, as Lord Lane CJ put it in the case of Viola (1982) 75 CR. App. R. 125, 128, 130;[1982] 3 All ER 73 , 76, 77. But as relevance is a matter of degree in each case, the question in reality is whether or not the evidence is or is not sufficiently relevant. For in order to keep criminal trials within bounds and to assist the jury in concentrating on what matters and not being distracted by doubts as to marginal events, it is necessary in the interests of justice to avoid multiplicity of issues where possible. In every case this is a matter for the trial judge on the evidence and on the way the case is put before him. When one comes to cross-examination, questions in cross-examination equally have to be relevant to the issues before the court, and those issues of course include the credibility of the witness giving evidence as to those issues. But a practical distinction must be drawn between questions going to an issue before the court and questions merely going either to the credibility of the witness or to facts that are merely collateral. Where questions go solely to the credibility of the witness or to collateral facts the general rule is that answers given to such questions are final and cannot be contradicted by rebutting evidence. This is because of the requirement to avoid multiplicity of issues in the overall interests of justice.
“Again, we cite from Cross [on Evidence] at p.283: “As relevance is a matter of degree it is impossible to devise an exhaustive means of determining when a question is collateral for the purpose of the rule under consideration …” “Pollock C.B. said in the leading case of Attorney General v Hitchcock (1847) 1 EXCH. 91-99: “… the test, whether the matter is collateral or not is this: if the answer of a witness is a matter which you would be allowed on your own part to prove in evidence – if it had such a connection with the issue, that you would be allowed to give it in evidence – then it is a matter on which you may contradict him.”
“It is important to recognise that, in dealing with a challenge to the Commission’s decision not to refer a case, particularly where that involves a claim that the Commission had reached a wrong view of the law, the court is not necessarily required to reach a conclusion on the competing legal arguments. If the assessment of the legal issues (and therefore the likely outcome of a reference) taken by the Commission is a tenable one, the court should not interfere, even if it considers that there is merit in the contrary view.”