Are there penalties for withholding self-exculpatory evidence during a trial?
<p>Suppose a person is put on trial for a crime, but he has video evidence showing his innocence.  Out of malice or spite of a personal nature towards his accuser, he allows the trial to proceed, and then at the last possible moment "discovers" and presents the evidence, leading to his acquittal and the accuser's extreme shock, dismay, and embarrassment.</p>

<p>Are there any sanctions that could be applied to the defendant if the court were convinced he had withheld that evidence in order to prolong the trial?</p>

<p>This is a good question, although it discusses crimes.  This answer generalizes the question by giving a response for <strong>civil violations</strong>.</p>

<p>In the <a href="/questions/tagged/united-states" class="post-tag" title="show questions tagged &#39;united-states&#39;" rel="tag">united-states</a>, where federal <a href="/questions/tagged/civil-procedure" class="post-tag" title="show questions tagged &#39;civil-procedure&#39;" rel="tag">civil-procedure</a> is followed and provided the tape isn't solely for impeachment purposes (<em>i.e.</em> it also documents other elements), there are certain disclosures required at the beginning of discovery governed by <a href="https://www.law.cornell.edu/rules/frcp/rule_26" rel="noreferrer">Rule 26(a)(1)(A)(ii)</a>.  </p>

<p>If a party withholds one of these disclosures, under <a href="https://www.law.cornell.edu/rules/frcp/rule_37" rel="noreferrer">Rule 37(c)(1)</a>, the court is able to take a number of actions, including throwing the evidence out.  This could, of course, result in the withholder's conviction.  Yet, if the court does not go to that extreme, it may impose the sanctions in <a href="https://www.law.cornell.edu/rules/frcp/rule_37" rel="noreferrer">Rule 37(b)</a>.</p>

<p>So the withholder's attorney might try to make a case that the evidence is, indeed, solely for impeachment purposes.</p>

<p>In the UK, when you are read your rights you are told that you don't have to say anything, but that it may harm your defence if you later rely in court on anything that you haven't mentioned. </p>

<p>The obvious reason is that if you make any claims that might prove you are innocent, the cops want to be able to verify those claims, which they can't if they hear of it in court for the first time. So that video could have been forged, but the cops can't prove it if it first shows up in court. I can't say what will happen, but I wouldn't be entirely surprised if a UK court threw that evidence out. If it happened, it couldn't happen to a more pleasant guy. </p>

<p>Yes, sanctions are possible. But not automatic.</p>

<p>"Trial by ambush" is not allowed in the U.S. Both sides have the right to know the evidence of the other side prior to trial. This process is called <strong><em>discovery</em></strong> and it is governed by a set of rules.</p>

<p>I suspect any possible sanctions in this case would be discretionary by the judge and legally justified by the defendant breaking the rules of discovery.</p>

<p>Surely any competent prosecutor would have asked the defendant to produce all exculpatory evidence using all the available tools of discovery. The defendant then would have had to have lied and claimed the evidence did not exist or produce the evidence prior to trial. Otherwise, the defendant risks sanctions including but not limited to having the evidence being ruled inadmissible or at least giving the prosector additional time to review the (previously withheld) evidence.</p>

<p>So, yes, the defendant is exposed to possible sanctions —  subject to the judge's discretion — if they broke the rules of discovery.</p>

<p>This type of litigation strategy is allowed in criminal cases for most kinds of evidence, but not all kinds of evidence. Discovery rules in criminal cases are not symmetrical. The prosecution has a duty to disclose evidence in advance to the defense, but the defense obligation to make disclosures prior to trial is much more limited.</p>
<p>The courts have, however, held that it is constitutional to require defendants to alert the prosecution to an intent to raise certain kinds of defenses if the defendant intends to rely upon them at trial because they change the nature of the evidence that needs to be presented by the prosecution.</p>
<p>Most commonly, the advanced disclosure rule applies to alibi evidence, an insanity defense, and/or presentation of expert testimony, but local practice varies.</p>
<p>If a defendant sought to present evidence that should have been disclosed prior to trial the court could either exclude the evidence as not timely disclosed, or grant a continuance to the prosecution postponing completion of the hearing to allow it time to prepare a rebuttal case, or could declare a mistrial caused by the acts of the defendant which would not prevent a retrial of the case. The decision made by the trial court judge regarding how to deal with the situation would be subject to abuse of discretion review by an appellate court.</p>
<p>Generally, if this is allowed at all, it would not be sanctionable, or improper.</p>
<p>It would be stupid to do this however, in most cases. In the United States, outside of Texas and a few other jurisdictions, the defendant has to pay for the cost of his criminal defense attorney, if he is able to do so, even if he wins at trial. The prosecution attorney is paid for by the state and not by the accuser. Until an acquittal is granted, the defendant is subject to serious limitations in the defendant's freedom prior to trial and may have to post a cash bond at economic cost (if the defendant can even afford to do so). Going through an entire trial when you don't need to do so, increases your out of pocket costs and restrictions on your rights.</p>
<p>If the exculpatory evidence is disclosed earlier in the case, if it is actually solid, it is likely that the prosecution will dismiss the case voluntarily, and even if it doesn't, in most felonies, it is possible for the judge to dismiss the case in a pre-trial hearing based upon exculpatory evidence prior to trial without risking having to face a jury that could go either way. This gives you two chances to have the exculpatory evidence believed, once before a judge and again before a jury.</p>

<p><strong>Are there penalties for withholding self-exculpatory evidence during a trial?</strong></p>
<p><a href="/questions/tagged/england-and-wales" class="post-tag" title="show questions tagged &#39;england-and-wales&#39;" rel="tag">england-and-wales</a></p>
<p><strong>Yes</strong>  A defendant may be liable to pay &quot;costs&quot; if convicted, or even acquitted, in certain circumstances.</p>
<p>The overriding principle is a <a href="https://www.legislation.gov.uk/ukpga/1998/42/schedule/1/part/I/chapter/5?timeline=false" rel="nofollow noreferrer">fair trial</a> and there are very few avenues for the prosecution to deny the inclusion of defence evidence - a video purporting to show the defendant's innocence is not one of them.</p>
<p>If a defendant introduces fresh evidence during his trial the prosecution can challenge it under cross examination or request an adjournment to consider it in detail before proceeding.   If they come to the conclusion that the evidence is sufficiently exculpatory then they should not continue with the current indictment by, for example, offering no evidence (ie dropping the case) or by amending the charge to one that has a realistic prospect of conviction based on all the available evidence.</p>
<p>If, on the other hand, the prosecution decide to continue with the original indictment the judge may direct the jury during his summing up to consider what are called the <a href="https://www.legislation.gov.uk/ukpga/1994/33/part/III/crossheading/inferences-from-accuseds-silence?timeline=false" rel="nofollow noreferrer">Adverse Inferences</a> - basically: if this fresh defence is genuine why wasn't given earlier, or has the defendant made it up?</p>
<p><strong>If he is acquitted</strong> then he may be liable to pay costs for any &quot;<a href="https://www.legislation.gov.uk/uksi/1986/1335/regulation/3/made" rel="nofollow noreferrer">Unnecessary or Improper Acts and Omissions</a>&quot;</p>
<p><strong>If he is convicted</strong> as well as being sentenced he and may also be liable to pay cost under, for example, <a href="https://www.legislation.gov.uk/ukpga/1985/23/part/II/crossheading/award-of-costs-against-accused?timeline=false" rel="nofollow noreferrer">s.18 of the Prosecution of Offences Act 1985</a>.</p>

criminal-law evidence suppression