You can build organisational structures to have the system more or less self-police, without controlling it exclusively from hard restrictions (see https://news.ycombinator.com/item?id=49372089).
Same way you build a company to coordinate people and get their best behaviour despite human nature to be lazy and greedy, you could design AI harnesses able to detect and discard agents going rogue and relaunch them with better guidance to prevent misaligned behaviour.