Your honor, there is precedence for this in Trek with the cases "Court Martial", "The Measure of a Man" and "Rules of Engagement" were in one of the attorneys had a personal relationship with either the accused or another member of the ship's crew.Once again, Starfleet picking officers for legal proceedings that have no business being there. The prosecutor is in a relationship with the accused Commanding officer! There are Jag officers whose job this actually is. Plus Patel is a Starship Captain, does she even have legal training? I know, rule of drama trumps all.
Also, in The Menagerie Kirk, Mendez and Pike all serve as tribunal members, despite two having very close relationship with Spock.