Witness credibility questions on cross-examination
<p>Dan is on trial for murdering Vanessa. Wayne, who is Dan's neighbour, is witness for the prosecution.</p>
<p>Dan's lawyer is interested to discredit Wayne's evidence, but has nothing.</p>
<p>On cross-examination, can Dan's lawyer question Wayne about his previous encounters/communication with Dan in the hope to uncover any reasons why Wayne would be biased against Dan? Like, for example, if they had a neighbours' feud or otherwise disliked each other?</p>
<p>On the one hand, such a question would not be relevant to the matter. On the other hand, Dan's lawyer could say it pertains to Wayne's bias and credibility, which is generally allowed on cross-examination.</p>
<p>Would the threshold be met? Can Dan's lawyer ask those questions merely because Wayne is Dan's neighbour? Or would he need to know of something more specific between Dan and Wayne?</p>
<p>Also, can Dan's lawyer just ask Wayne if he had any criminal history / convictions? Normally the state prosecutor will have access to this info and have to provide it to the defence. But in some cases (e.g. private prosecution) this info is not available unless the witness releases it.</p>
<p>(Any jurisdiction where laws about this are/derived from common law)</p>

<p>In the United States, this would be pretty uncontroversial as a legal matter. A witness's bias speaks to his credibility, and the general rule is that a witness's credibility is always relevant.</p>
<p>Dan would therefore have a reasonable amount of freedom to make inquiries into these matters, but he can probably expect the judge to shut it down before too long if he doesn't have any basis for suggesting a credibility issue and the questioning isn't revealing anything, either.</p>
<p>I wouldn't necessarily expect a court to find it objectionable to ask about the specific issues you've raised, either. If there have been neighbor disputes, Dan is entitled to let the jury know. The court would likely allow an inquiry into Wayne's criminal record, as well, though it would probably be limited to questions about crimes that are admissible under <a href="https://www.law.cornell.edu/rules/fre/rule_609" rel="nofollow noreferrer">Rule 609</a>.</p>
<p>As a tactical matter, though, this approach can be risky, and I think most lawyers would not recommend it. The general rule is that at trial, you don't ask a witness a question that you don't know the answer to. Opening up this line of questioning blind could go wrong in several ways. Dan could ask Wayne fifty questions about his credibility, but if there's nothing there, all Dan has done is make Wayne look <em>more</em> credible. Alternatively, the lawyer could ask Wayne if he has any criminal record, and he could answer, &quot;Oh yes. Dan and I were convicted for trying unsuccessfully to kill Alice a couple years ago.&quot; Not a great answer.</p>

<p>The Privy Council recently summarised the common law in relation to cross-examination on credit, in <em>Clarke v The State</em> <a href="https://www.jcpc.uk/cases/docs/jcpc-2017-0012-judgment.pdf" rel="nofollow noreferrer">[2021] UKPC 16</a> at [40]:</p>
<blockquote>
<p>At common law, therefore, the judge had a discretion to permit cross-examination as to credit. In exercising that discretion he was required to have regard to whether such questions would seriously affect the jury’s view of the credibility of the witness, to whether the misconduct relied upon had a solid foundation, to the fairness to the witness of permitting such cross-examination and to whether such cross-examination would be a distraction from the real issues in the case. An appellate court may not interfere with the exercise of such a discretion unless it is clearly wrong or wrong in principle.</p>
</blockquote>
<p>Because it is a matter of discretion, it is not possible to say definitively whether the proposed questions are permissible “merely because Wayne is Dan's neighbour.” However, questions about whether the witness is biased against a party are generally allowed. In <em>Attorney-General v Hitchcock</em> <a href="http://www.commonlii.org/uk/cases/EngR/1847/616.pdf" rel="nofollow noreferrer">(1847) 154 ER 38</a> at 42, Pollock CB said:</p>
<blockquote>
<p>It is certainly allowable to ask a witness in what manner he stands affected towards the opposite party in the cause, and whether he does not stand in such a relation to that person as is likely to affect him, and prevent him from having an unprejudiced state of mind, and whether he has not used expression importing that he would be revenged on someone, or that he would give such evidence as might dispose of the cause in one way or the other.</p>
</blockquote>
<p>As for the admissibility of convictions to impeach the credit of a witness: “there is not a little obscurity about the extent of the common-law principle concerning the use of convictions for this purpose. It must be remembered that until the <a href="https://books.google.com.au/books?id=zsUuAAAAIAAJ&amp;pg=RA1-PA188&amp;lpg=RA1-PA188" rel="nofollow noreferrer"><em>Evidence Act 1843</em></a> conviction of felony or any crimen falsi rendered a man incompetent as a witness. This limited the possible occasions of the question arising”: <em>Bugg v Day</em> <a href="https://www.austlii.edu.au/au/cases/cth/HCA/1949/59.html" rel="nofollow noreferrer">(1949) 79 CLR 442</a> at 465. Thus, the admissibility of such evidence depends on the statute law of the jurisdiction in question and cannot be determined solely by reference to the common law.</p>
<p>However, by the time of Wigmore’s <em>Treatise on the Law of Evidence</em> (16th ed, 1899), it was possible to say (<a href="https://archive.org/details/atreatiseonlawe01harrgoog/page/n722/mode/1up" rel="nofollow noreferrer">at 578</a>):</p>
<blockquote>
<p>… proof by the record of conviction of crime is universally conceded to be a proper mode of impeachment. As to what kinds of crimes may here be employed, there is no general agreement. When conviction as a ground for total disqualification was abolished by statute, the statute usually provided for the use of such evidence in impeachment, and accordingly the statute often indicates the precise range allowable. Where it does not, the question may arise whether the kinds of crime are to be the same as were formerly sufficient to disqualify, or whether they are to be limited to those which affect the trait of veracity. In most jurisdictions the former solution is reached.</p>
</blockquote>
<p>There is one other principle which should be noted, since the question suggests that cross-examining counsel might ask speculative questions “in the hope to uncover any reasons why Wayne would be biased against Dan.” There is a potential ethical problem here if the questions have no basis (ie. they are not even supported by Dan’s instructions). Lord Reid summarised the relevant principle in Rondel v Worsley <a href="https://www.bailii.org/uk/cases/UKHL/1967/5.html" rel="nofollow noreferrer">[1969] 1 AC 191</a>, at 227:</p>
<blockquote>
<p>Every counsel has a duty to his client fearlessly to raise every issue, advance every argument, and ask every question, however distasteful, which he thinks will help his client's case. But, as an officer of the Court concerned in the administration of justice, he has an overriding duty to the Court, to the standards of his profession, and to the public, which may and often does lead to a conflict with his client's wishes or with what the client thinks are his personal interests. Counsel must not mislead the Court, <strong>he must not lend himself to casting aspersions on the other party or witnesses for which there is no sufficient basis in the information in his possession</strong>, he must not withhold authorities or documents which may tell against his clients but which the law or the standards of his profession require him to produce.</p>
</blockquote>

common-law witnesses cross-examination