It's an ingenious strategy to fill your prisons so full of enemy soldiers, that you run out of places to put them, causing a crisis in the prison system budget. Eventually the financial strain of housing them will bankrupt you, you'll have to set them all free. The released prisoners will then rise up and takeover the entire realm all at once.
Pure genius.
That's why you privatize your prison system. Then the judge gets in bed with the corporations running it and you find yourself starting more and more wars so you can fuel your need for fresh inmates to keep your economy going.
