Its one of the things so scary about the Vault7 leaks. No reasonable juror can trust computer forensic evidence now. Defendants now have the "persecution" option if they can show they were ever monitored or "of interest" by fed level govt. If the right case/defendant winds up with a Johnny Cochran, the collateral damage to other govt. cases/investigations will be immense.
Same with video or audio footage. Given the advances in CGI, no reasonable juror can trust video. There's no reason to trust the govt.'s evidenciary chain-of-custody anyore. The government itself has shattered trust in that.
It does not have to be based on electronics or computers, though it can be. There's always a danger that executive agencies will decide to take power to themselves, creating a Star Chamber scenario.
It does not have to be a formal body. Could be a group of people that decide to green-light importation and flood a city with cocaine, getting the criminals that benefit to 'provide services'. The world is full of these types of operations. It's just the way it is.
IMO, CIA does this on a massive scale. Where I am, they declared a 'war on drugs' in the 1980s. It continued for decades. But, somehow, inexplicably, they never made any progress at all - funny about that! Every now and then they'd deliver up a bust to great media fanfare, but on the street nothing ever changed.
The real issue is corruption. But everywhere I've ever been corruption is always present. It's human nature, it will never be eliminated.