Wait wait wait, so I finally went back to see how Leah ended up in jail for me. I had assumed it was because I approached Arthur for information on Valerie/Amiran instead of asking him to back off of Leah. This confused me since the whole point of the dinner was to get that information, but ok.
I replayed from Chapter 15 and it was never even an option to bring up Leah. Instead, the sole deciding factor in whether Leah ends up in jail...is saying you were a better highschool president candidate than Sam. WTF? I get that you running for president was the lowest point in your relationship with Leah, but come on man