Why not ask the NSA? I thought they recorded everything.
Anyway, I would think the mother-in-law has the messages he sent her.
They are NOT going to admit this in court EVER.
Last time they tried to muscle Apple into not only providing a fig leaf for that one case, but for every case in the future.
They only backed off when it was claimed an Israeli company could crack the code, that gave them enough of a fig leaf to justify the information they had already illegally collected, along with all the data from every phone call and text and post YOU and I made.
As noted above, there is no proof they even used the Israeli company...