All evidence must be “authenticated” before it’s introduced at trial. Authentication, according to Black’s Law Dictionary, is “the act of proving that something…is true or genuine.”
In Massachusetts,
To satisfy the requirement of authenticating or identifying an item of evidence, the proponent must produce evidence sufficient to support a finding that the item is what the proponent claims it is. See Section 901(a) of the Massachusetts Guide to Evidence.
Typically this is easily done through the testimony of a witness who has firsthand knowledge of the evidence.
Complications may arise, however, when a lawyer seeks to introduce electronic communications (such as emails and text messages) at trial.
The fact that a witness or alleged victim received messages on her phone or computer does not, by itself, prove that those messages were sent by the defendant.
According to Massachusetts case law,
In the case of a digital communication that is relevant only if authored by the defendant, a judge is required to determine whether there is sufficient evidence to persuade a reasonable trier of fact that it is more likely than not that the defendant was the author of the communication. See Commonwealth v. Meola, 95 Mass. App. Ct. 303, 308 (2019).
Moreover,
Evidence that the defendant’s name is written as the author of an [electronic communication] that bears the defendant’s name is not sufficient alone to authenticate the electronic communication as having been authored or sent by the defendant. See Commonwealth v. Purdy, 459 Mass. 442, 450 (2011).
Those seeking to authenticate electronic communication must show
some ‘confirming circumstances’ sufficient for a reasonable jury to find by a preponderance of the evidence that the defendant authored the [electronic communications]. Id.
For more on electronic communication, see my post When Are Email and Electronic Signatures Legally Binding in Massachusetts?