I’m currently replaying the first game ready for the third one and trying to get full Legend score and I wondered if anyone knows what stats or decisions stop you from being able to say that you don’t trust your sidekick at the first opportunity. I was playing Lawful/Fame/Offensive/Team Player and the option was greyed out. Does your relationship percentage affect it?
I believe so yes. The lower your relationship with your sidekick can mean you don’t trust them or you just don’t like them for some reason. A little off topic here but why do you have to distrust your sidekick to get the best legend score? I mean a hero would treat their sidekick with respect and kindness right or is there something I missed?
Have you completed the game yet? Can I talk about the story with spoilers?
You did include “possible spoilers” in the thread title, so it’s safe to say that everyone who sees this thread has already been duly warned about any spoilers you might mention. In short, go ahead. 
Sorry completely forgot to reply to this 
Basically your sidekick is working against you because Sparrow is Prodigal in disguise, Pressie is working for Prodigal and Tamara Rain, if I remember correctly, is being threatened to work against you by Prodigal.
Hope that clears everything up 
I think choosing Sparrow as your sidekick actually makes it harder to distrust her since she and the player character share the same background and therefore have a higher relationship stat. I think I remember having a harder time getting the relationship stat low enough with Sparrow than with Tarana or Pressie. I could be wrong, though. In general, you need to have a low relationship with your sidekick in order to be suspicious of them, so just be mean to them like the bully you are (I’m kidding).
Choosing Tarana as your sidekick will present more opportunities to be mean to her since she does a lot of stupid things. I remember that after breaking up the ani-gang fight with your sidekick, Pressie and Sparrow just leave and you don’t have a chance to say anything mean, but you do get a chance to yell at Tarana for doing something stupid. Also, Tarana suspects that you only chose her because her parents own some sort of news outlet, so she has a lower relationship with you from the get-go.
I hope that helps. 
I got it eventually thanks