It’s not about proving it beyond a doubt, the OP’s frustrarion is about how the whole courtroom drama was inaccurate.
The assumtion is this: Legally, Starfleet only allows sapent adults to join its ranks. So a toaster cannot be a starfleet officer, and neither can a dog.
The fact that he is an officer means that in legal terms, Starfleet has already decided that he is a person, and any court that asks this question has a quick and easy answer.
I am eagerly awaiting real daily-driver support for these chips. So much potential for Linux tablets, phones, as well as the power-efficiency of Chromebooks and such.