That's one way. Another is to have an uncle who retired as a fairly senior federal LEO, and kept some material for his personal protection, much the way Director Hoover did. After following the boss's example is the path to attaboys and promotion, right.
Long ago when I asked him about such things, he counseled me against following in his foosteps; even his own agency had more than its share of incompetence, corruption and coverup, and had sunk to a standard lower than he had always held himself. By way of a present and legacy, after his death I got some of the material he'd kept. More I got by horsetrading information related to what I was interested in. And there were others in state and local law enforcement who hadc a pretty good idea of what had happened.
My own respect for law enforcement and the judicial system was horribly shaken by my experiences.
In the end, nobody won and I was financially ruined.
My days were miserable and my nights were nightmares of fear, loathing and the desire to get even, Night after night I formulated dreams of battles where I was victorious over my foes.
After a couple years I went to see a doctor and got help. After a couple years I managed to put my life back together and my loss was only financial, my family stayed intact and I was a changed man. Stronger, smarter and confident.
All this happened because I refused to compromise my integrity and I fought back, but not very smartly or rationally.
I did not win my revenge, but they did not compromise me. In effect, they lost.
If you are carrying this burden around like I did, then you need to end it. It will hurt you.
But I digress.....................................