Earlier quoted context omitted.
Yes, it's unheard of for agents in a "different investigative team" (that, BTW, happens to be involved in shaking down suspects) to, say, provide illegally obtained evidence to their coworkers. The government is very strict about tracking the source of evidence so it can be turned over to the defense; otherwise it'd be a clear Brady violation. They could face as much as a light chastizement from a federal judge! http…
Is there some link you can point us to suggesting that that's happened in this case? There are 113,000 employees at DOJ, so, statistically, every case is always going to be one or two hops away from some kind of malfeasance somewhere, right?
It is entirely likely, a priori, that there will be abuses in a system where violations of the law are, to a close approximation, unpunished, it is to their great professional benefit to violate the law, and it is to their great professional benefit to ignore violations of the law by their coworkers. Nothing in this indictment makes me revise that opinion downwards.
Besides which, these agents in particular have a pattern (according to the indictment) of initiating investigations against targets who had become obstacles to their corruption.