This is a complicated question and probably not the most interesting subject to most. That being said, with regards to accusatory instruments, it is a very important concern.
With the growing reliance on electronic signatures, this type of question was bound to arise. Although there is not unanimous agreement on this matter, at least one court in New York has ruled that electronic signatures on depositions are valid under CPL 100.20. To clarify, in New York, Criminal Procedure Law 100.20 requires that a supporting deposition be “subscribed and verified” while CPL 100.30 describes how a supporting deposition may be verified. Specifically, under 100.30(1)(d), the supporting deposition “may bear a form notice that false statements made therein are punishable as a class A misdemeanor pursuant to section 210.45 of the penal law, and such form notice together with the subscription of the deponent constitute a verification of the instrument.”
So the first question here is whether the police officer can use an electronic signature. Again, although this issue is not settled, in one case a trial court found electronic signatures are valid so long as the supporting deposition bears the required language of CPL.100.30(1)(d), as it relates to false statements. Therefore, at least one court has rejected the argument that an accusatory instrument is defective solely because the electronic signature violates the verification requirement.
Another interesting question arising from this situation involves the timing. Specifically, what if the electronic signature is affixed before the officer even makes the allegations? Given that an officer could proceed to write anything in the factual allegations once the electronically signed deposition is printed out, does this mean the deposition fails to satisfy the verification requirement?
At least one court has stated that electronically signing a deposition before writing any factual allegations does not violate the verification requirement. The court reasoned the act of printing out an electronic supporting deposition and filing a copy with the appropriate court is enough to affirm the contents of the deposition. As a result, it complies with CPL 100.20.
Nevertheless, concerns remain with regards to the timing of the signature. At the very least, the best practice would be to avoid affirming the contents of a deposition until the “contents” are actually included in the document.