admissible or not
<p>The prosecutor has the conversation from an anonymous app, only from the device of the accuser. Has nothing from the accused and the conversation doesn't identify the accused. The only thing identifying the accused is an IP address the account used 6 months after the crime, is this enough evidence to charge and/or use this conversation as evidence? obviously they also have the testimony of the accuser.The investigation failed to get the accused device, or records from the company. The account has a username and nothing identifying the would be defendant. I have seen cases use the defendants phone as evidence with little else but can't find anything where the accusers phone was used when it did not identify the person being accused. Is this because it is not admissible due to lack of authentication of the conversation?</p>

<blockquote>
<p>is this enough evidence to charge and/or use this conversation as
evidence? obviously they also have the testimony of the accuser.</p>
</blockquote>
<h1>Short Answer</h1>
<p>Yes. And, the accuser's telephone data, together with the accuser's testimony, is admissible evidence which is sufficient to bring charges.</p>
<h1>Long Answer</h1>
<p>To bring charges, all that the prosecutor must show to proceed to trial and to comply with the professional ethics standards that apply to lawyers is to show &quot;probable cause&quot; which is a much lower standard than the proof beyond a reasonable doubt that is necessary to obtain a conviction.</p>
<p>The testimony of the accuser alone is almost always going to be sufficient to charge someone with a crime that would involve a &quot;conversation&quot; of some kind, and to convict someone of that crime.</p>
<p>The evidence from the phone would usually be admissible and would corroborate the accusers testimony, which might increase the likelihood that a jury would find that the evidence taken as a whole constituted proof beyond a reasonable doubt, even though the phone alone, without the accuser's testimony, probably wouldn't suffice to establish proof beyond a reasonable doubt unless the content of the conversation was sufficient to identify the defendant (e.g. because it mentioned things that only the defendant could have known).</p>
<p>It is not at all uncommon to use an accuser's phone as evidence in a criminal prosecution where that kind of communication has something to do with the crime that the defendant is charged with (of course, most crimes are far less articulate like physically trespassing, punching somebody, shoplifting, burglary, etc.). The side of the conservation that allegedly involved the defendant would normally not be subject to the hearsay rule, for example, because it would be the alleged statement of a party-opponent.</p>
<p>If the accuser was involved in the conversation, the testimony of the accuser is also sufficient in most cases to authenticate evidence from a phone that sets forth the conversation because the testimony of the accuser corroborates the evidence from the phone.</p>
<p>Basically, all the accuser has to do is testify credibly that the phone was not tampered with and that the data on the phone is not fake to the best of the accuser's knowledge and that the accuser believed that the conservation was related to the crime.</p>
<p>The evidence should be at least admissible for the purpose of showing that a conversation took place with someone at the times indicated at the IP addresses indicated (assuming that the jury believes that accuser's testimony that it is authentic) even if it doesn't, by itself, prove that the defendant was the other person involved in the conversation. The existence of the conservation and nature of the conservation is one of the things that the prosecution needs to prove in your hypothetical case, and if proves that, even if this evidence doesn't by itself prove the defendant's identity, it is still relevant to proving part of the case, which reduces the amount of the case that has to be established with other kinds of evidence.</p>
<p>The fact that the conversation alleged by the accuser actually happened and is corroborated by digital evidence makes it more likely that the accuser is telling the truth and that the defendant is guilty, even if this single piece of evidence by itself doesn't prove the entire case.</p>
<p>The defense can certainly urge the jury consider the fact that the phone evidence isn't very rigorously linked to the defendant as they make the argument that there isn't proof beyond a reasonable doubt that the defendant is guilty, but the jury, considering the totality of the evidence in which the phone evidence and the testimony of the accuser corroborate each other, find that the proof beyond a reasonable doubt standard has been met.</p>
<p><strong>There Will Almost Always Be Some Other Evidence</strong></p>
<p>Also, usually, in any prosecution based in part upon a &quot;conservation&quot; by telephone or text message, there will be other evidence from context, timing, the defendant's motive, etc. that provides further circumstantial evidence that the defendant committed the crime that may also be considered, even if it doesn't &quot;feel&quot; like other evidence in the sense that it is testimony from someone else or additional physical evidence.</p>
<p>In many cases, even though a defendant has a right to remain silent and not present any witnesses and not have that held against him, a defendant that fails to present some kind of evidence to overcome latent circumstantial evidence that tends to point to his guilt is usually going to be found guilty by a jury beyond a reasonable doubt.</p>
<p>For example, the fact that the defendant was in a place where he could have used the IP address in question, rather than having an alibi is probably not, by itself, proof beyond a reasonable doubt, but is circumstantial evidence that can remove one source of doubt from the other evidence. (Obviously, if he does have an alibi or subpoenas records to show that the IP address in question was available at the location where he was six months earlier, the case against him becomes much weaker.)</p>
<p>The fact that the defendant lived at the same location six months earlier is relevant and corroborates the testimony, even if one doesn't definitively establish that the ISP address was the same six months earlier. This removes some doubt that the other evidence might have left hanging.</p>
<p>The fact that the conversation is something that the defendant could have said, while probably not proof beyond a reasonable doubt by itself, is circumstantial evidence that can remove a source of doubt from the other evidence. (Obviously, if the conversation is, for example, in Farsi, and the defendant doesn't know how to speak Farsi and doesn't even have access to a Farsi dictionary or translation program, in contrast, proof of a case against him beyond a reasonable doubt may be impossible.)</p>
<p>Similarly, if the defendant can't offer any plausible narrative in which someone else could plausibly have been using the IP address at the times in question and could have said the things that were said in the conversation, that too, while probably not proof beyond a reasonable doubt by itself, is circumstantial evidence that can remove a source of doubt from the other evidence. (Obviously, if there was someone else who could have done it instead of the defendant, this weakens the prosecution's case.)</p>

united-states criminal-law evidence prosecutorial-discretion digital-forensics