>>>Unable to become a police officer because of a past felony conviction, a man finds his own way as a maverick bounty hunter to fight for the justice he never got.

All of that is either backstory which means it’s (mostly) off screen.? But a logline is about what is shown on screen. ? Or, alternatively, all of that is part of the setup which means it occurs in the first act.

So the story — what the logline should focus on — seems to begin when he goes undercover in a town full of criminals.

>> while in pursuit of their target

Who, specifically, are they looking for?? And what are the stakes?? Is he going undercover for the “justice he never got” or for the reward money as a maverick bounty hunter?? And what is the “justice he never got” — what does that mean?

A protagonist can certainly have an interesting past that motivates his present actions.? But there isn’t enough space in a logline to cram all that in and a logline is about the present, what the protagonist must do now, not what he may have done — or had done to him — in the past.