I don't think that's what GP's refering to. In an adversarial system you can either have dedicated prosecutors, or have the state hire an attorney to prosecute

I don't think that's what GP's refering to. In an adversarial system you can either have dedicated prosecutors, or have the state hire an attorney to prosecute the case just as the defendant hires an attorney. Both would draw from the same pool of criminal attorneys. AIUI, this was historically the case in England and Wales.