You need to front the capital to start the investigation, though. This is like saying that you can pay for asteroid mining by mining asteroids. That's true! You just need a few billion dollars to mine that first asteroid.
Like startups, criminal prosecutions don't have a 100% success rate. The system, despite its flaws, has a lot of protection for defendants. So you're basically asking the taxpayers to speculate on your pet project. Sometimes they do, sometimes they don't.
> Like startups, criminal prosecutions don't have a 100% success rate.
Here we're primarily talking about collecting civil forfeitures. DOJ can go scoop up assets they find, and defendants can try and claw them back (and the DOJ only requires a preponderance of the evidence to keep the money).