Talk:Federal Security Service/@comment-80.42.19.88-20151218180706/@comment-1028741-20151218200817
Players can't, although they can join the Federal Navy Auxiliary by completing Rank-up missions for the Federal Navy (and the same for the Empire).
You can fight alongside the Federal Security Service against criminals by going bounty hunting in a Federation system anywhere but a Compromised Nav Beacon or Resource Extraction Site (Hazardous) - they don't go into those as they are too dangerous. It's not joining them, but at least you can aid and be aided by them.
As far as the recruitment process for Federal Security Service NPCs in the game's lore, I don't know. With them being cops I'd imagine they have some sort of selection process, but considering the Federal Navy keep offering me rank-up missions despite the Federation being my current #2 priority enemy faction (after Emperor's Dawn) and me having killed hundreds of Federal Navy ships in conflict zones (and some outside) I have doubts about Federal recruitment vetting processes.
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